{"id":149,"date":"2024-06-17T22:07:46","date_gmt":"2024-06-17T13:07:46","guid":{"rendered":"https:\/\/rakuha.com\/?p=149"},"modified":"2024-06-17T22:07:49","modified_gmt":"2024-06-17T13:07:49","slug":"seccon-beginners-ctf-2024-writeup","status":"publish","type":"post","link":"https:\/\/rakuha.com\/?p=149","title":{"rendered":"SECCON Beginners CTF 2024 writeup"},"content":{"rendered":"\n<p>\u4e45\u3057\u3076\u308a\u306e\u6295\u7a3f\u3067\u3059\u3002\u6700\u8fd1CTF\u304b\u3089\u96e2\u308c\u6c17\u5473\u3067\u3057\u305f\u304c\u3001\u5b50\u80b2\u3066\u304c\u843d\u3061\u7740\u3044\u3066\u304d\u305f\u306e\u3067\u3001CTF\u306b\u53c2\u52a0\u3057\u306f\u3058\u3081\u307e\u3057\u305f\u3002<br>\u306a\u304a\u3001\u521d\u65e5\u306f\u5b50\u4f9b\u304c\u516c\u5712\u3067\u904a\u3093\u3067\u3044\u308b\u4e2dCTF\u3057\u3066\u307e\u3057\u305f\uff08\u4ed6\u306e\u89aa\u5fa1\u3055\u3093\u3001\u5927\u5909\u52a9\u304b\u308a\u307e\u3057\u305f\uff09<br>\u4eca\u56de\u306f6\u554f\uff08welcome\u3092\u542b\u3081\u308b\u30687\u554f\uff09\u3092\u6b63\u89e3\u3057\u3001524pt\u3067168\u4f4d\u3067\u3057\u305f\u3002<\/p>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_82_2 counter-hierarchy ez-toc-counter ez-toc-light-blue ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\"><p class=\"ez-toc-title\" style=\"cursor:inherit\">\u76ee\u6b21<\/p>\n<\/div><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/rakuha.com\/?p=149\/#miscgetRank\" >[misc]getRank<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/rakuha.com\/?p=149\/#miscclamre\" >[misc]clamre<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/rakuha.com\/?p=149\/#webwooorker\" >[web]wooorker<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/rakuha.com\/?p=149\/#webssrforlfi\" >[web]ssrforlfi<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/rakuha.com\/?p=149\/#webwooorker2\" >[web]wooorker2<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/rakuha.com\/?p=149\/#pwnablesimpleoverflow\" >[pwnable]simpleoverflow<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/rakuha.com\/?p=149\/#%E8%A7%A3%E3%81%8D%E3%81%9F%E3%81%8B%E3%81%A3%E3%81%9F%E5%95%8F%E9%A1%8C\" >\u89e3\u304d\u305f\u304b\u3063\u305f\u554f\u984c<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/rakuha.com\/?p=149\/#%E3%81%95%E3%81%84%E3%81%94%E3%81%AB\" >\u3055\u3044\u3054\u306b<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"miscgetRank\"><\/span>[misc]getRank<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"715\" height=\"832\" src=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-1.png?resize=715%2C832&#038;ssl=1\" alt=\"\" class=\"wp-image-151\" srcset=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-1.png?w=715&amp;ssl=1 715w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-1.png?resize=258%2C300&amp;ssl=1 258w\" sizes=\"auto, (max-width: 715px) 100vw, 715px\" \/><\/figure>\n\n\n\n<p>\u6570\u5b57\u3092\u4e88\u60f3\u3057\u3066\u3001\u4e00\u81f4\u3057\u3066\u3044\u305f\u3089\u30b9\u30b3\u30a2\u304c\u52a0\u7b97\u3055\u308c\u3066\u3044\u304f\u30b2\u30fc\u30e0\u3002<br>\u3067\u3001\u73fe\u5728\u306e\u30b9\u30b3\u30a2\u306b\u5fdc\u3058\u3066\u30e9\u30f3\u30ad\u30f3\u30b0\u304c\u6c7a\u307e\u3063\u3066\u3044\u3066\u3001\u30e9\u30f3\u30ad\u30f3\u30b0\u306e1\u4f4d\u306b\u306a\u308c\u3070\u898b\u4e8b\u30d5\u30e9\u30b0\u3092\u30b2\u30c3\u30c8\u3067\u304d\u308b\u30b7\u30b9\u30c6\u30e0\u3002<br><br>\u30d5\u30e9\u30b0\u3092\u30b2\u30c3\u30c8\u3059\u308b\u306e\u306b\u306f\u4ee5\u4e0b\u306e\u6761\u4ef6\u304c\u5fc5\u8981<br>\u30fb\u30b9\u30b3\u30a2\u304c10\u306e255\u4e57\u3088\u308a\u5927\u304d\u3044\u3053\u3068\uff08\u305f\u3060\u3057\u3001\u30b9\u30b3\u30a2\u304c10\u306e255\u4e57\u3088\u308a\u5927\u304d\u3044\u5834\u5408\u306f\u30b9\u30b3\u30a2\u309210\u306e100\u4e57\u3092\u5272\u3063\u305f\u6570\u304c\u30b9\u30b3\u30a2\u3068\u306a\u308b\uff09<br>\u30fb\u30b9\u30b3\u30a2\u306f300\u6587\u5b57\u4ee5\u5185<\/p>\n\n\n\n<p>\u30b9\u30b3\u30a2\u3092\u52a0\u7b97\u3059\u308b\u90e8\u5206\u306f\u30b5\u30fc\u30d0\u3068\u901a\u4fe1\u3057\u3066\u3044\u306a\u3044\u306e\u3067\u3001\u3053\u3061\u3089\u306f\u6539\u3056\u3093\u3057\u653e\u984c\u3002\u554f\u984c\u306f10\u306e255\u4e57\u3088\u308a\u5927\u304d\u3044\u5024\u306b\u3057\u306a\u3051\u308c\u3070\u3044\u3051\u306a\u3044\u304c\u300110\u306e255\u4e57\u3088\u308a\u5927\u304d\u3044\u5834\u5408\u3001\u30b9\u30b3\u30a2\u304c10\u306e100\u4e57\u3067\u5272\u3063\u305f\u5024\u3068\u306a\u3063\u3066\u3057\u307e\u3046\u306e\u3067\u3001\u30d5\u30e9\u30b0\u3092\u3068\u308b\u306b\u306f10\u306e355\u4e57\u4ee5\u4e0a\u306e\u6570\u304c\u5fc5\u8981\u306b\u306a\u308a\u3001\u6b63\u653b\u6cd5\u3067\u306f\u3044\u3051\u306a\u3044\u3053\u3068\u304c\u308f\u304b\u3063\u305f\u3002<\/p>\n\n\n\n<p>\u30b5\u30fc\u30d0\u5074\u306e\u30bd\u30fc\u30b9\u3092\u898b\u308b\u3068\u30ea\u30af\u30a8\u30b9\u30c8\u3068\u3057\u3066\u6e21\u3055\u308c\u305f\u30b9\u30b3\u30a2\u306e\u6587\u5b57\u5217\u3092parseInt\u3067\u6570\u5024\u306b\u5909\u63db\u3057\u3066\u51e6\u7406\u3092\u884c\u3063\u3066\u3044\u308b\u306e\u3067\u3001\u305d\u3053\u306b\u4f55\u304b\u3042\u308b\u306e\u3067\u306f\u306a\u3044\u304b\u3068parseInt\u306e\u4ed5\u69d8\u3092\u8abf\u3079\u3066\u307f\u308b\u3053\u3068\u306b\u3002<\/p>\n\n\n\n<p>\u3059\u308b\u3068\u3001parseInt\u306e\u7b2c\u4e8c\u5f15\u6570\uff08\u57fa\u6570\uff09\u3092\u6307\u5b9a\u3057\u3066\u3044\u306a\u3044\u5834\u5408\u3001\u5165\u529b\u5024\u30920x\u304b\u3089\u59cb\u3081\u308b\u306816\u9032\u6570\u3067\u89e3\u91c8\u3057\u3066\u304f\u308c\u308b\u3068\u3044\u3046\u3053\u3068\u304c\u308f\u304b\u3063\u305f\u3002<\/p>\n\n\n\n<p>\u305d\u306e\u305f\u3081\u3001\u30b9\u30b3\u30a2\u306e\u6587\u5b57\u5217\u30920xFFFFF&#8230;\u3068300\u6587\u5b57\u3074\u3063\u305f\u308a\u306b\u306a\u308b\u3088\u3046\u306b\u3057\u3066\u3001\u30ea\u30af\u30a8\u30b9\u30c8\u3092\u9001\u4fe1\u3057\u305f\u3068\u3053\u308d\u3001\u30d5\u30e9\u30b0\u3092\u30b2\u30c3\u30c8\u3057\u305f\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"miscclamre\"><\/span>[misc]clamre<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"741\" height=\"473\" src=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-2.png?resize=741%2C473&#038;ssl=1\" alt=\"\" class=\"wp-image-152\" srcset=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-2.png?w=741&amp;ssl=1 741w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-2.png?resize=300%2C191&amp;ssl=1 300w\" sizes=\"auto, (max-width: 741px) 100vw, 741px\" \/><\/figure>\n\n\n\n<p>\u3053\u3061\u3089\u306fflag.ldb\u306e\u5185\u5bb9\u304c\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u306a\u3063\u3066\u304a\u308a\u30010\/^\u304b\u3089\u59cb\u307e\u308b\u90e8\u5206\u304c\u30b7\u30b0\u30cd\u30c1\u30e3\u306e\u30d1\u30bf\u30fc\u30f3\u306b\u306a\u3063\u3066\u3044\u308b\u3088\u3046\u306b\u898b\u3048\u308b\u3002<br>\u203b\\x63\\x74\\x66\u304cctf\u306b\u306a\u3063\u3066\u3044\u308b\u3002<\/p>\n\n\n\n<p><code>ClamoraFlag;Engine:81-255,Target:0;1;63746634;0\/^((\\x63\\x74\\x66)(4)(\\x62)({B)(\\x72)(\\x33)\\3(\\x6b1)(\\x6e\\x67)(\\x5f)\\3(\\x6c)\\11\\10(\\x54\\x68)\\7\\10(\\x480)(\\x75)(5)\\7\\10(\\x52)\\14\\11\\7(5)})$\/<\/code><\/p>\n\n\n\n<p>\u6700\u521d\u306f\u3088\u304f\u308f\u304b\u3089\u306a\u304b\u3063\u305f\u306e\u3067\u3059\u304c\u3001\u9014\u4e2d\u304b\u3089\u3042\u308b\\\u306e\u5f8c\u306b\u6570\u5b57\u304c\u3042\u308b\u5834\u5408\u306f\u6b63\u898f\u8868\u73fe\u306e\u30ab\u30c3\u30b3\u306b\u5bfe\u5fdc\u3057\u3066\u3044\u308b\u3053\u3068\u304c\u308f\u304b\u308a\u3001\u305d\u308c\u3092\u3082\u3068\u306b\u89e3\u8aad\u3057\u305f\u7d50\u679c\u3001\u30d5\u30e9\u30b0\u3092\u30b2\u30c3\u30c8\u3059\u308b\u3053\u3068\u306b\u6210\u529f\u3057\u305f\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"webwooorker\"><\/span>[web]wooorker<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"791\" height=\"459\" src=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-3.png?resize=791%2C459&#038;ssl=1\" alt=\"\" class=\"wp-image-153\" srcset=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-3.png?w=791&amp;ssl=1 791w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-3.png?resize=300%2C174&amp;ssl=1 300w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-3.png?resize=768%2C446&amp;ssl=1 768w\" sizes=\"auto, (max-width: 791px) 100vw, 791px\" \/><\/figure>\n\n\n\n<p>\u30da\u30fc\u30b8\u306b\u30a2\u30af\u30bb\u30b9\u3057\u3066\u3082\u300cNo token provided. You need to login .\u300d\u3068\u8868\u793a\u3055\u308c\u308b\u3060\u3051\u3002login\u304c\u5fc5\u8981\u306a\u306e\u3060\u304c\u3001\u7ba1\u7406\u8005\u6a29\u9650\u3067\u30ed\u30b0\u30a4\u30f3\u3057\u306a\u3044\u3068\u30d5\u30e9\u30b0\u3092\u7372\u5f97\u3067\u304d\u306a\u3044\u3002<\/p>\n\n\n\n<p>\u8106\u5f31\u6027\u5831\u544abot\u306e\u307b\u3046\u306f\u5831\u544a\u3059\u308bURL\u306b\u30a2\u30af\u30bb\u30b9\u3059\u308b\u3068\u7ba1\u7406\u8005\u6a29\u9650\u3067\u30ed\u30b0\u30a4\u30f3\u3059\u308b\u3068\u3044\u3046\u30af\u30ed\u30fc\u30e9\u306b\u306a\u3063\u3066\u3044\u308b\u3002\u307e\u305f\u3001\u30ed\u30b0\u30a4\u30f3\u753b\u9762\u306e\u30bd\u30fc\u30b9\u3067\u306f\u3001\u30ed\u30b0\u30a4\u30f3\u306b\u6210\u529f\u3059\u308b\u3068next\u3068\u3044\u3046\u30af\u30a8\u30ea\u30d1\u30e9\u30e1\u30fc\u30bf\u306b\u8a2d\u5b9a\u3055\u308c\u305fURL\u306b\u9077\u79fb\u3057\u3066\u304a\u308a\u3001\u305d\u306e\u969b\u306btoken\u304c\u30af\u30a8\u30ea\u30d1\u30e9\u30e1\u30fc\u30bf\u306b\u4ed8\u4e0e\u3055\u308c\u308b\u3088\u3046\u306a\u52d5\u304d\u3068\u306a\u3063\u3066\u3044\u305f\u3002<\/p>\n\n\n\n<p>\u306a\u306e\u3067\u3001Webhook.site\u3068\u3044\u3046\u30b5\u30a4\u30c8\u3092\u4f7f\u3063\u3066\u3001\u305d\u306e\u30ea\u30af\u30a8\u30b9\u30c8\u3092\u53d7\u3051\u53d6\u308d\u3046\u3068\u3057\u305f\u3068\u3053\u308d\u3001\u306a\u305c\u304b\u3046\u307e\u304f\u53d7\u3051\u53d6\u308c\u305a\u3001\u7d50\u5c40\u3053\u306e\u30d6\u30ed\u30b0\u30b5\u30a4\u30c8\u306eURL\u3092\u8a2d\u5b9a\u3057\u3066\u3001\u30a2\u30af\u30bb\u30b9\u30ed\u30b0\u304b\u3089token\u306e\u30af\u30a8\u30ea\u30d1\u30e9\u30e1\u30fc\u30bf\u3092\u53d6\u5f97\u3057\u307e\u3057\u305f\u3002<\/p>\n\n\n\n<p><code>[15\/Jun\/2024:23:04:15 +0900] \"GET \/?token=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6ImFkbWluIiwiaXNBZG1pbiI6dHJ1ZSwiaWF0IjoxNzE4NDYwMjUzLCJleHAiOjE3MTg0NjM4NTN9.xRMU0Xt1Bmfp6r7-9Mr-4-BgjqAZqDE8kvqoZ2v0VZc HTTP\/2.0\" 200 11179 \"http:\/\/wooorker:34466\/\" \"Mozilla\/5.0 (X11; Linux x86_64) AppleWebKit\/537.36 (KHTML, like Gecko) HeadlessChrome\/125.0.6422.26 Safari\/537.36\"<\/code><\/p>\n\n\n\n<p>\u305d\u306etoken\u3092\u305d\u306e\u307e\u307e\u30af\u30a8\u30ea\u30d1\u30e9\u30e1\u30fc\u30bf\u306b\u8a2d\u5b9a\u3057\u3066\u81ea\u5206\u306e\u30d6\u30e9\u30a6\u30b6\u304b\u3089\u30a2\u30af\u30bb\u30b9\u3059\u308b\u3053\u3068\u3067\u30d5\u30e9\u30b0\u30b2\u30c3\u30c8\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"webssrforlfi\"><\/span>[web]ssrforlfi<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"756\" height=\"381\" src=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-4.png?resize=756%2C381&#038;ssl=1\" alt=\"\" class=\"wp-image-156\" style=\"width:840px;height:auto\" srcset=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-4.png?w=756&amp;ssl=1 756w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-4.png?resize=300%2C151&amp;ssl=1 300w\" sizes=\"auto, (max-width: 756px) 100vw, 756px\" \/><\/figure>\n\n\n\n<p>\u30b5\u30a4\u30c8\u3092\u898b\u308b\u3068\u3001<code>?url=xxxx<\/code>\u3067\u6307\u5b9a\u3057\u305fURL\u306b\u30a2\u30af\u30bb\u30b9\u3057\u3066\u3001\u305d\u306e\u30da\u30fc\u30b8\u306e\u5185\u5bb9\u3092\u8868\u793a\u3059\u308b\u3089\u3057\u3044\u3002<\/p>\n\n\n\n<p>\u809d\u5fc3\u306e\u30d5\u30e9\u30b0\u306f\u74b0\u5883\u5909\u6570\u306b\u8a2d\u5b9a\u3055\u308c\u3066\u304a\u308a\u3001\u305d\u306e\u5185\u5bb9\u3092\u3069\u3046\u3084\u3063\u3066\u53d6\u5f97\u3059\u308b\u304b\u3068\u3044\u3046\u3082\u306e\u3002<\/p>\n\n\n\n<p>url\u306b\u4f7f\u7528\u3067\u304d\u308b\u30b9\u30ad\u30fc\u30de\u306fhttp\u304bhttps\u304bfile\u3057\u304b\u9078\u3079\u305a\u3001http\u3084https\u306e\u5834\u5408\u3001localhost\u304c\u7981\u6b62\u3055\u308c\u3066\u3044\u3066\u3001file\u30b9\u30ad\u30fc\u30de\u306e\u5834\u5408\u3060\u3068\u3001file:\/\/\u4ee5\u964d\u306e\u30d1\u30b9\u304c\u5b9f\u5728\u3059\u308b\u30d5\u30a1\u30a4\u30eb\u3060\u3068\u30a8\u30e9\u30fc\u3067\u3042\u308a\u3001\u304b\u3064<code>..<\/code>\u306e\u4f7f\u7528\u3082\u7981\u6b62\u3055\u308c\u3066\u3044\u308b\u3002<\/p>\n\n\n\n<p>file\u30b9\u30ad\u30fc\u30de\u306e\u4ed5\u69d8\u3092\u8abf\u3079\u3066\u307f\u305f\u3068\u3053\u308d\u3001file:\/\/\u306e\u5f8c\u306blocalhost\/\u3068\u3064\u3051\u308b\u3053\u3068\u304c\u3067\u304d\u308b\u3089\u3057\u3044\uff08file:\/\/\/\u306flocalhost\u3092\u7701\u7565\u3057\u305f\u3082\u306e\u3089\u3057\u3044\uff09\u306e\u3067\u3001<code>https:\/\/ssrforlfi.beginners.seccon.games\/?url=file:\/\/localhost\/proc\/self\/environ<\/code> \u306b\u30a2\u30af\u30bb\u30b9\u3057\u3001\u74b0\u5883\u5909\u6570\u306e\u5185\u5bb9\u304b\u3089\u30d5\u30e9\u30b0\u3092\u30b2\u30c3\u30c8\u3057\u305f\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"webwooorker2\"><\/span>[web]wooorker2<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"773\" height=\"467\" src=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-5.png?resize=773%2C467&#038;ssl=1\" alt=\"\" class=\"wp-image-157\" srcset=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-5.png?w=773&amp;ssl=1 773w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-5.png?resize=300%2C181&amp;ssl=1 300w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-5.png?resize=768%2C464&amp;ssl=1 768w\" sizes=\"auto, (max-width: 773px) 100vw, 773px\" \/><\/figure>\n\n\n\n<p>\u3053\u3061\u3089\u306f\u5148\u307b\u3069\u306ewooorker\u3092\u9032\u5316\u3055\u305b\u305f\u3082\u306e\u3002<br>\u4fee\u6b63\u5dee\u5206\u3092\u898b\u308b\u3068\u30ed\u30b0\u30a4\u30f3\u306b\u6210\u529f\u3059\u308b\u3068next\u3068\u3044\u3046\u30af\u30a8\u30ea\u30d1\u30e9\u30e1\u30fc\u30bf\u306b\u30c8\u30fc\u30af\u30f3\u3092\u8a2d\u5b9a\u3057\u3066URL\u9077\u79fb\u3057\u3066\u3044\u305f\u90e8\u5206\u304c\u3001\u30d5\u30e9\u30b0\u30e1\u30f3\u30c8\u8b58\u5225\u5b50\u306b\u306a\u3063\u3066\u3044\u305f\u3002<br>flag.html\uff08\u3068flag.js\uff09\u306f\u305d\u306e\u30d5\u30e9\u30b0\u30e1\u30f3\u30c8\u8b58\u5225\u5b50\u304b\u3089\u30c8\u30fc\u30af\u30f3\u3092\u53d6\u5f97\u3057\u3066<code>\/flag<\/code>\u306b\u30a2\u30af\u30bb\u30b9\u3057\u3066\u3044\u305f\u306e\u3067\u3001\u305d\u306e\u30bd\u30fc\u30b9\u3092\u81ea\u5206\u306e\u30b5\u30fc\u30d0\u306b\u304a\u3044\u3066\u3001<code>\/flag<\/code>\u3092\u53d6\u5f97\u3059\u308b\u969b\u306b\u30af\u30a8\u30ea\u30d1\u30e9\u30e1\u30fc\u30bf\u306b\u30c8\u30fc\u30af\u30f3\u3092\u4ed8\u4e0e\u3057\u3066\u30a2\u30af\u30bb\u30b9\u3059\u308b\u3088\u3046\u306b\u3057\u3066\u3001\u81ea\u5206\u306e\u30b5\u30fc\u30d0\u306e\u30a2\u30af\u30bb\u30b9\u30ed\u30b0\u304b\u3089\u30c8\u30fc\u30af\u30f3\u3092\u53d6\u5f97\u3057\u305f\u3002<\/p>\n\n\n\n<p><code>[16\/Jun\/2024:09:59:03 +0900] \"GET \/flag?token=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6ImFkbWluIiwiaXNBZG1pbiI6dHJ1ZSwiaWF0IjoxNzE4NDk5NTQ0LCJleHAiOjE3MTg1MDMxNDR9.EhRYzoN71n7uZwrV0uV2Pr_jST6Nxqg0kcOKjKVj8rQ HTTP\/2.0\" 404 1299 \"https:\/\/rakuha.com\/hoge\/flag.html\" \"Mozilla\/5.0 (X11; Linux x86_64) AppleWebKit\/537.36 (KHTML, like Gecko) HeadlessChrome\/125.0.6422.26 Safari\/537.36\"<\/code><\/p>\n\n\n\n<p>\u305d\u306e\u30c8\u30fc\u30af\u30f3\u3092\u540c\u3058\u3088\u3046\u306b\u30d5\u30e9\u30b0\u30e1\u30f3\u30c8\u8b58\u5225\u5b50\u3068\u3057\u3066\u8a2d\u5b9a\u3057\u305f\u3046\u3048\u3067\u81ea\u5206\u306e\u30d6\u30e9\u30a6\u30b6\u304b\u3089\u30a2\u30af\u30bb\u30b9\u3059\u308b\u3053\u3068\u3067\u30d5\u30e9\u30b0\u30b2\u30c3\u30c8\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"pwnablesimpleoverflow\"><\/span>[pwnable]simpleoverflow<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"803\" height=\"370\" src=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-6.png?resize=803%2C370&#038;ssl=1\" alt=\"\" class=\"wp-image-158\" srcset=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-6.png?w=803&amp;ssl=1 803w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-6.png?resize=300%2C138&amp;ssl=1 300w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-6.png?resize=768%2C354&amp;ssl=1 768w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2024\/06\/image-6.png?resize=800%2C369&amp;ssl=1 800w\" sizes=\"auto, (max-width: 803px) 100vw, 803px\" \/><\/figure>\n\n\n\n<p>\u30b3\u30fc\u30c9\u306f\u4ee5\u4e0b\u306e\u3068\u304a\u308a\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>int main() {\n  char buf&#91;10] = {0};\n  int is_admin = 0;\n  printf(\"name:\");\n  read(0, buf, 0x10);\n  printf(\"Hello, %s\\n\", buf);\n  if (!is_admin) {\n    puts(\"You are not admin. bye\");\n  } else {\n    system(\"\/bin\/cat .\/flag.txt\");\n  }\n  return 0;\n}<\/code><\/pre>\n\n\n\n<p>\u5909\u6570buf\u306bread\u3067\u5165\u529b\u3057\u305f\u6587\u5b57\u3092\u5165\u308c\u3066\u3044\u308b\u304c\u3001buf\u306f10byte\u3057\u304b\u78ba\u4fdd\u3055\u308c\u3066\u304a\u3089\u305a\u3001read\u306f0x10\u306a\u306e\u306716byte\u8aad\u307f\u8fbc\u3080\u3053\u3068\u304b\u3089\u300110\u6587\u5b57\u4ee5\u4e0a\u9069\u5f53\u306b\u5165\u308c\u308c\u3070\u3001is_admin\u306e\u5909\u6570\u306e\u5185\u5bb9\u304c\u4e0a\u66f8\u304d\u3055\u308c\u3001\u30d5\u30e9\u30b0\u306e\u5185\u5bb9\u304c\u8aad\u307f\u8fbc\u3081\u308b\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E8%A7%A3%E3%81%8D%E3%81%9F%E3%81%8B%E3%81%A3%E3%81%9F%E5%95%8F%E9%A1%8C\"><\/span>\u89e3\u304d\u305f\u304b\u3063\u305f\u554f\u984c<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>\u30fb[crypto]Safe Prime<br>\u3000\u4eca\u307e\u3067CTF\u3067crypto\u306b\u306f\u624b\u3092\u51fa\u305b\u305a\u306b\u3044\u305f\u304c\u3001\u3088\u3046\u3084\u304f\u89e3\u304d\u65b9\u304c\u308f\u304b\u3063\u3066\u304d\u305f\u3002<br>\u30002p^2 + p = n\u3068\u3044\u3046\u65b9\u7a0b\u5f0f\u3092\u89e3\u3051\u3070\u3044\u3044\u3068\u3044\u3046\u3068\u3053\u308d\u307e\u3067\u308f\u304b\u3063\u305f\u304c\u3001\u3053\u3053\u304b\u3089\u3046\u307e\u304f\u8a08\u7b97\u3067\u304d\u305a\u30bf\u30a4\u30e0\u30a2\u30c3\u30d7\u3002\u6b21\u56de\u306f\u306a\u3093\u3068\u304b\u3068\u308a\u305f\u3044\u3002\u3002\u3002<\/p>\n\n\n\n<p>\u30fb[reversing]assemble<br>\u3000\u3088\u304f\u308f\u304b\u3089\u306a\u304b\u3063\u305f\u304c\u3001ChatGPT\u541b\u306b\u52a9\u3051\u3066\u3082\u3089\u3044\u306a\u304c\u3089\u6700\u7d42\u554f\u984c\u307e\u3067\u3044\u3063\u305f\u3051\u3069\u3001\u305d\u3053\u3067\u3046\u307e\u304f\u3044\u304b\u305a\u632b\u6298\u3002<br>\u3000\u6614\u3068\u9055\u3063\u3066\u308f\u304b\u3089\u306a\u3044\u3053\u3068\u304c\u3042\u3063\u3066\u3082ChatGPT\u541b\u306b\u805e\u3051\u3070\u3042\u308b\u7a0b\u5ea6\u3044\u3044\u3068\u3053\u308d\u307e\u3067\u306f\u3044\u3051\u308b\u4e16\u754c\u7dda\u304c\u898b\u3048\u305f\u306e\u3067\u3001\u6614\u3068\u9055\u3063\u3066\u5909\u308f\u3063\u305f\u306a\u30fc\u3068\u601d\u3063\u305f<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E3%81%95%E3%81%84%E3%81%94%E3%81%AB\"><\/span>\u3055\u3044\u3054\u306b<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>\u4eca\u56de\u306f\u4e45\u3057\u3076\u308a\u306b\u96c6\u4e2d\u3057\u3066CTF\u306b\u53d6\u308a\u7d44\u3080\u3053\u3068\u304c\u3067\u304d\u307e\u3057\u305f\u3002<br>CTF\u3092\u901a\u3058\u3066\u65b0\u3057\u3044\u4ed5\u69d8\u3092\u77e5\u3063\u305f\u308a\u3001\u65b0\u3057\u3044\u6280\u8853\u3092\u77e5\u3063\u305f\u308a\u3068\u697d\u3057\u307f\u306a\u304c\u3089\u52c9\u5f37\u3067\u304d\u308b\u306e\u3067\u975e\u5e38\u306b\u3088\u3044\u7d4c\u9a13\u3068\u306a\u308a\u307e\u3057\u305f\u3002<br>\u307e\u305f\u4eca\u5f8c\u3082\uff08\u5c11\u3057\u7c21\u5358\u306a\uff09CTF\u306b\u53c2\u52a0\u3057\u3066\u3044\u304d\u305f\u3044\u3067\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e45\u3057\u3076\u308a\u306e\u6295\u7a3f\u3067\u3059\u3002\u6700\u8fd1CTF\u304b\u3089\u96e2\u308c\u6c17\u5473\u3067\u3057\u305f\u304c\u3001\u5b50\u80b2\u3066\u304c\u843d\u3061\u7740\u3044\u3066\u304d\u305f\u306e\u3067\u3001CTF\u306b\u53c2\u52a0\u3057\u306f\u3058\u3081\u307e\u3057\u305f\u3002\u306a\u304a\u3001\u521d\u65e5\u306f\u5b50\u4f9b\u304c\u516c\u5712\u3067\u904a\u3093\u3067\u3044\u308b\u4e2dCTF\u3057\u3066\u307e\u3057\u305f\uff08\u4ed6\u306e\u89aa\u5fa1\u3055\u3093\u3001\u5927\u5909\u52a9\u304b\u308a\u307e\u3057\u305f\uff09\u4eca\u56de\u306f6\u554f\uff08welcome&hellip; <span class=\"clear\"><\/span><a href=\"https:\/\/rakuha.com\/?p=149\" class=\"more-link read-more\" rel=\"bookmark\"><span class=\"screen-reader-text\">SECCON Beginners CTF 2024 writeup<\/span><i class=\"fa fa-arrow-right\"><\/i> \u306e\u7d9a\u304d\u3092\u8aad\u3080<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[2],"tags":[13,14,15],"class_list":["post-149","post","type-post","status-publish","format-standard","hentry","category-ctf","tag-ctf","tag-ctf4b","tag-seccon"],"aioseo_notices":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/rakuha.com\/index.php?rest_route=\/wp\/v2\/posts\/149","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rakuha.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rakuha.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rakuha.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/rakuha.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=149"}],"version-history":[{"count":6,"href":"https:\/\/rakuha.com\/index.php?rest_route=\/wp\/v2\/posts\/149\/revisions"}],"predecessor-version":[{"id":162,"href":"https:\/\/rakuha.com\/index.php?rest_route=\/wp\/v2\/posts\/149\/revisions\/162"}],"wp:attachment":[{"href":"https:\/\/rakuha.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=149"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rakuha.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=149"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rakuha.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=149"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}