{"id":46,"date":"2019-05-27T23:17:10","date_gmt":"2019-05-27T14:17:10","guid":{"rendered":"https:\/\/rakuha.com\/?p=46"},"modified":"2019-06-01T06:52:07","modified_gmt":"2019-05-31T21:52:07","slug":"seccon-for-beginners-ctf-2019-writeup","status":"publish","type":"post","link":"https:\/\/rakuha.com\/?p=46","title":{"rendered":"SECCON for Beginners CTF 2019 writeup"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">SECCON for Beginners CTF\u306b\u53c2\u52a0\u3057\u307e\u3057\u305f\u3002<br>CpawCTF\u304c\u5927\u4f53\u89e3\u3051\u308b\u3088\u3046\u306b\u306a\u3063\u3066\u3001\u6311\u3093\u3060\u306e\u306b\u3042\u307e\u308a\u89e3\u3051\u305a\u306b\u843d\u3061\u8fbc\u3093\u3067\u307e\u3059&#8230;<br>\u3082\u3046\u5c11\u3057\u3001\u9811\u5f35\u308a\u305f\u3044\u3068\u601d\u3044\u307e\u3059\u3002\u5099\u5fd8\u9332\u306e\u305f\u3081\u3001Writeup\u3092\u66f8\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_85 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=46\/#Reversing\" >Reversing<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/rakuha.com\/?p=46\/#warmup_Seccompare\" >[warmup] Seccompare<\/a><\/li><\/ul><\/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=46\/#Crypto\" >Crypto<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/rakuha.com\/?p=46\/#warmup_So_Tired\" >[warmup] So Tired<\/a><\/li><\/ul><\/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=46\/#Misc\" >Misc<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/rakuha.com\/?p=46\/#warmup_Welcome\" >[warmup] Welcome<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/rakuha.com\/?p=46\/#containers\" >containers<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/rakuha.com\/?p=46\/#Dump\" >Dump<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Reversing\"><\/span>Reversing<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"warmup_Seccompare\"><\/span>[warmup] Seccompare<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p>https:\/\/score.beginners.seccon.jp\/files\/seccompare_44d43f6a4d247e65c712d7379157d6a9.tar.gz<\/p><\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">\u3068\u308a\u3042\u3048\u305afile\u30b3\u30de\u30f3\u30c9\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-bash\" data-lang=\"Bash\"><code>$ file seccompare\nseccompare: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter \/lib64\/ld-linux-x86-64.so.2, for GNU\/Linux 3.2.0, BuildID[sha1]=4a607c82ea263205071c80295afe633412cda6f7, not strippe<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u3068\u308a\u3042\u3048\u305aobjdump\u3057\u307e\u3057\u305f\u3002main\u3042\u305f\u308a\u3092\u8272\u3005\u898b\u3066\u304f\u3068\u3001\u3053\u306e\u8fba\u304c\u602a\u3057\u305d\u3046\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"765\" height=\"931\" src=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/Screenshot_2019-05-26-rakuyou-1-PaizaCloud-Instant-Linux-with-Web-UI.png?resize=765%2C931&#038;ssl=1\" alt=\"\" class=\"wp-image-48\" srcset=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/Screenshot_2019-05-26-rakuyou-1-PaizaCloud-Instant-Linux-with-Web-UI.png?w=765&amp;ssl=1 765w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/Screenshot_2019-05-26-rakuyou-1-PaizaCloud-Instant-Linux-with-Web-UI.png?resize=247%2C300&amp;ssl=1 247w\" sizes=\"auto, (max-width: 765px) 100vw, 765px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">movb\u306e\u90e8\u5206\u306e$0x??\u306e\u90e8\u5206\u3092ascii\u30b3\u30fc\u30c9\u306b\u5bfe\u5fdc\u3055\u305b\u3066\u307f\u308b\u3068\u3001\u30d5\u30e9\u30b0\u3092\u30b2\u30c3\u30c8\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ctf4b{5tr1ngs_1s_n0t_en0ugh}<\/pre>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Crypto\"><\/span>Crypto<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"warmup_So_Tired\"><\/span>[warmup] So Tired<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p> \u6700\u5f37\u306e\u6697\u53f7\u3092\u4f5c\u308a\u307e\u3057\u305f\u3002 \u6697\u53f7\u3088\u304f\u308f\u304b\u3089\u306a\u3044\u3051\u3069\u304d\u3063\u3068\u5927\u4e08\u592b\uff01<br> File: so_tired.tar.gz <\/p><\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">encrypted.txt\u304c\u3042\u3063\u305f\u306e\u3067\u3001\u3068\u308a\u3042\u3048\u305a\u4e2d\u3092\u898b\u3066\u307f\u308b\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">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<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u3068\u308a\u3042\u3048\u305abase64\u3067\u30c7\u30b3\u30fc\u30c9\u3057\u3066\u307f\u308b\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-bash\" data-lang=\"Bash\"><code>$ cat encrypted.txt | base64 -d &gt; encrypted<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u306e\u5f8c\u3001file\u30b3\u30de\u30f3\u30c9\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-bash\" data-lang=\"Bash\"><code>$ file encrypted\nencrypted: zlib compressed data<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">zlib\u5f62\u5f0f\u3060\u3068\u308f\u304b\u308b\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8abf\u3079\u308b\u3068Python\u304c\u697d\u3063\u307d\u3044\u306e\u3067\u3001Python\u3067\u5c55\u958b\u3059\u308b\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-python\" data-lang=\"Python\"><code>import base64\nimport zlib\n\ns = &#39;\uff1cencrypted.txt\u306e\u4e2d\u8eab\uff1e&#39;\n\nprint s.decode(&quot;base64&quot;).decode(&quot;zlib&quot;)<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u5b9f\u884c\u3057\u3066\u3001\u7121\u4e8b\u7d42\u308f\u308a\u304b\u306a\u3068\u601d\u3063\u305f\u3089\u3001\u518d\u5ea6base64\u306e\u5185\u5bb9\u304c\u8868\u793a\u3055\u308c\u308b\u3002\u307e\u3055\u304b\u306d\u3002\u3068\u3044\u3046\u308f\u3051\u3067\u7121\u9650\u30eb\u30fc\u30d7\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-python\" data-lang=\"Python\"><code>import base64\nimport zlib\n\ns = &#39;\uff1cencrypted.txt\u306e\u4e2d\u8eab\uff1e&#39;\n\nwhile True:\n\ts = s.decode(&quot;base64&quot;).decode(&quot;zlib&quot;)\n\tprint s<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u7121\u4e8b\u3001\u30d5\u30e9\u30b0\u3092\u30b2\u30c3\u30c8\u3067\u304d\u307e\u3057\u305f\u3002\uff08\u4ed6\u306e\u4eba\u306ewriteup\u3092\u898b\u308b\u3068\u3001500\u56de\u304f\u3089\u3044\u7e70\u308a\u8fd4\u3055\u308c\u3066\u3044\u305f\u3068\u304b\u3002\u3002\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ctf4b{very_l0ng_l0ng_BASE64_3nc0ding}<\/pre>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Misc\"><\/span>Misc<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"warmup_Welcome\"><\/span>[warmup] Welcome<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p> SECCON Beginners CTF\u306eIRC\u30c1\u30e3\u30f3\u30cd\u30eb\u3067\u4f1a\u3044\u307e\u3057\u3087\u3046\u3002<br> IRC: <code>freenode.net #seccon-beginners-ctf<\/code><\/p><\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">IRC\u306e\u30c1\u30e3\u30f3\u30cd\u30eb\u306b\u53c2\u52a0\u3057\u3066\u3001\u30d8\u30c3\u30c0\u306e\u3042\u305f\u308a\u3092\u898b\u308c\u3070OK\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ctf4b{welcome_to_seccon_beginners_ctf}<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"containers\"><\/span>containers<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p> Let&#8217;s extract files from the container.<br><a href=\"https:\/\/score.beginners.seccon.jp\/files\/e35860e49ca3fa367e456207ebc9ff2f_containers\">https:\/\/score.beginners.seccon.jp\/files\/e35860e49ca3fa367e456207ebc9ff2f_containers<\/a> <\/p><\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">\u30c0\u30a6\u30f3\u30ed\u30fc\u30c9\u3057\u3066\u3001\u30d0\u30a4\u30ca\u30ea\u3067\u898b\u3066\u307f\u308b\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1598\" height=\"981\" src=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/stirling.png?fit=900%2C553&amp;ssl=1\" alt=\"\" class=\"wp-image-54\" srcset=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/stirling.png?w=1598&amp;ssl=1 1598w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/stirling.png?resize=300%2C184&amp;ssl=1 300w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/stirling.png?resize=768%2C471&amp;ssl=1 768w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/stirling.png?resize=1024%2C629&amp;ssl=1 1024w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/stirling.png?resize=800%2C491&amp;ssl=1 800w\" sizes=\"auto, (max-width: 900px) 100vw, 900px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">FILE0.\u306e\u5f8c\u306bPNG\u306e\u30c7\u30fc\u30bf\u304c\u3064\u3044\u3066\u3044\u308b\u3088\u3046\u306b\u898b\u3048\u308b\u3002\u4ee5\u964d\u3001\u305d\u308c\u304c\u9023\u7d9a\u3057\u3066\u3044\u308b\u3002\u306a\u306e\u3067\u3001Stirling\u3092\u4f7f\u3063\u3066\u3001\u90e8\u5206\u7684\u306b\u5225\u30d5\u30a1\u30a4\u30eb\u306b\u3057\u3066\u3044\u304f\u3002\u9806\u756a\u306b\u753b\u50cf\u3092\u4e26\u3079\u308b\u3068\u3001\u7b54\u3048\u304c\u51fa\u3066\u304f\u308b\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1193\" height=\"517\" src=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/\u7d50\u679c.png?fit=900%2C390&amp;ssl=1\" alt=\"\" class=\"wp-image-57\" srcset=\"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/%E7%B5%90%E6%9E%9C.png?w=1193&amp;ssl=1 1193w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/%E7%B5%90%E6%9E%9C.png?resize=300%2C130&amp;ssl=1 300w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/%E7%B5%90%E6%9E%9C.png?resize=768%2C333&amp;ssl=1 768w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/%E7%B5%90%E6%9E%9C.png?resize=1024%2C444&amp;ssl=1 1024w, https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/%E7%B5%90%E6%9E%9C.png?resize=800%2C347&amp;ssl=1 800w\" sizes=\"auto, (max-width: 900px) 100vw, 900px\" \/><\/figure>\n\n\n\n<pre class=\"wp-block-preformatted\">ctf4b{e52df60c058746a66e4ac4f34db6fc81}<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Dump\"><\/span>Dump<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p> Analyze dump and extract the flag!!<br> <a href=\"https:\/\/score.beginners.seccon.jp\/files\/fc23f13bcf6562e540ed81d1f47710af_dump\">https:\/\/score.beginners.seccon.jp\/files\/fc23f13bcf6562e540ed81d1f47710af_dump<\/a><\/p><\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">\u3068\u308a\u3042\u3048\u305afile\u30b3\u30de\u30f3\u30c9<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-bash\" data-lang=\"Bash\"><code>$ file fc23f13bcf6562e540ed81d1f47710af_dump\nfc23f13bcf6562e540ed81d1f47710af_dump: tcpdump capture file (little-endian) - version 2.4 (Ethernet, capture length 262144)<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u62e1\u5f35\u5b50\u3092pcap\u306b\u3057\u3066\u3001Wireshark\u3067\u958b\u304f\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3059\u308b\u3068\u3001hexdump\u3067\u30d5\u30e9\u30b0\u306e\u4e2d\u8eab\u3092\u53d6\u5f97\u3057\u3066\u3044\u308b\u901a\u4fe1\u304c\u3042\u308b\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">\/webshell.php?cmd=hexdump -e '16\/1 \"%02.3o \" \"\\n\"' \/home\/ctf4b\/flag<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u30ec\u30b9\u30dd\u30f3\u30b9\u306f\u3053\u3093\u306a\u611f\u3058\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-html\" data-lang=\"HTML\"><code>&lt;html&gt;\n&lt;head&gt;\n&lt;title&gt;Web Shell&lt;\/title&gt;\n&lt;\/head&gt;\n&lt;pre&gt;\n037 213 010 000 012 325 251 134 000 003 354 375 007 124 023 133\n...\n050 241 022 115 000 060 014 000                        \n&lt;\/pre&gt;\n&lt;\/html&gt;<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">hexdump\u306e\u30b3\u30de\u30f3\u30c9\u3092\u898b\u308b\u3068\u30018\u9032\u6570\u306b\u306a\u3063\u3066\u3044\u308b\u3002<br>\u306a\u306e\u3067\u3001pre\u3067\u56f2\u307e\u308c\u305f\u7bc4\u56f2\u3092\u629c\u304d\u51fa\u3057\u3001\u5225\u30d5\u30a1\u30a4\u30eb\u306b\u4fdd\u5b58\u3057\u3001\u30d0\u30a4\u30ca\u30ea\u306b\u5909\u63db\u3059\u308bSolver\u3092\u66f8\u3044\u3066\u307f\u308b\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-csharp\" data-lang=\"C#\"><code>    class Program\n    {\n        static void Main(string[] args)\n        {\n            using (StreamReader sr = new StreamReader(@&quot;C:\\Users\\rakuha\\Downloads\\ctg_beginners\\Misc\\Dump\\data.txt&quot;))\n            {\n                using (FileStream fs = new FileStream(@&quot;C:\\Users\\rakuha\\Downloads\\ctg_beginners\\Misc\\Dump\\output&quot;, FileMode.Create))\n                {\n                    string line = null;\n                    while ((line = sr.ReadLine()) != null)\n                    {\n                        string[] values = line.Split(new char[] { &#39; &#39; }, StringSplitOptions.RemoveEmptyEntries);\n                        foreach (string value in values)\n                        {\n                            int num = Convert.ToInt32(value, 8);\n                            fs.WriteByte((byte)num);\n                        }\n                    }\n                }\n            }\n        }\n    }\n<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u3067\u304d\u305f\u30d5\u30a1\u30a4\u30eb\u3092file\u30b3\u30de\u30f3\u30c9\u3067\u898b\u3066\u307f\u308b\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-bash\" data-lang=\"Bash\"><code>$ file output\noutput: gzip compressed data, last modified: Sun Apr  7 10:46:34 2019, from Unix<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">tar.gz\u3060\u3063\u305f\u306e\u3067\u3001\u5c55\u958b\u3059\u308b\u3002<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-bash\" data-lang=\"Bash\"><code>$ tar xzvf output\n.\/._flag.jpg\nflag.jpg<\/code><\/pre><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">flag.jpg\u3092\u8868\u793a\u3059\u308b\u3068\u3001\u30d5\u30e9\u30b0\u304c\u66f8\u3044\u3066\u3042\u308b\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">ctf4b{hexdump_is_very_useful}<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>SECCON for Beginners CTF\u306b\u53c2\u52a0\u3057\u307e\u3057\u305f\u3002CpawCTF\u304c\u5927\u4f53\u89e3\u3051\u308b\u3088\u3046\u306b\u306a\u3063\u3066\u3001\u6311\u3093\u3060\u306e\u306b\u3042\u307e\u308a\u89e3\u3051\u305a\u306b\u843d\u3061\u8fbc\u3093\u3067\u307e\u3059&#8230;\u3082\u3046\u5c11\u3057\u3001\u9811\u5f35\u308a\u305f\u3044\u3068\u601d\u3044\u307e\u3059\u3002\u5099\u5fd8\u9332\u306e\u305f\u3081\u3001Writeup\u3092\u66f8&hellip; <span class=\"clear\"><\/span><a href=\"https:\/\/rakuha.com\/?p=46\" class=\"more-link read-more\" rel=\"bookmark\"><span class=\"screen-reader-text\">SECCON for Beginners CTF 2019 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":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[2],"tags":[13,14,15],"class_list":["post-46","post","type-post","status-publish","format-standard","hentry","category-ctf","tag-ctf","tag-ctf4b","tag-seccon"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<meta name=\"author\" content=\"\u3089\u304f\u306f\u3002\"\/>\n\t<meta name=\"google-site-verification\" content=\"I_JXw338RMBFTetbO8o1Zw6x6zpg9_FAVU7TCeD1E-4\" \/>\n\t<meta name=\"keywords\" content=\"ctf,ctf4b,seccon\" \/>\n\t<link rel=\"canonical\" href=\"https:\/\/rakuha.com\/?p=46\" \/>\n\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 4.9.10\" \/>\n\t\t<meta property=\"og:locale\" content=\"ja_JP\" \/>\n\t\t<meta property=\"og:site_name\" content=\"Rakuha&#039;s Blog\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"SECCON for Beginners CTF 2019 writeup | Rakuha&#039;s Blog\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/rakuha.com\/?p=46\" \/>\n\t\t<meta property=\"og:image\" content=\"https:\/\/rakuha.com\/wp-content\/uploads\/2019\/05\/\u7d50\u679c.png\" \/>\n\t\t<meta property=\"og:image:secure_url\" content=\"https:\/\/rakuha.com\/wp-content\/uploads\/2019\/05\/\u7d50\u679c.png\" \/>\n\t\t<meta property=\"og:image:width\" content=\"1193\" \/>\n\t\t<meta property=\"og:image:height\" content=\"517\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2019-05-27T14:17:10+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2019-05-31T21:52:07+00:00\" \/>\n\t\t<meta name=\"twitter:card\" content=\"summary\" \/>\n\t\t<meta name=\"twitter:site\" content=\"@rakuha3\" \/>\n\t\t<meta name=\"twitter:title\" content=\"SECCON for Beginners CTF 2019 writeup | Rakuha&#039;s Blog\" \/>\n\t\t<meta name=\"twitter:image\" content=\"https:\/\/rakuha.com\/wp-content\/uploads\/2019\/05\/\u7d50\u679c.png\" \/>\n\t\t<script type=\"application\/ld+json\" class=\"aioseo-schema\">\n\t\t\t{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?p=46#article\",\"name\":\"SECCON for Beginners CTF 2019 writeup | Rakuha's Blog\",\"headline\":\"SECCON for Beginners CTF 2019 writeup\",\"author\":{\"@id\":\"https:\\\/\\\/rakuha.com\\\/?author=1#author\"},\"publisher\":{\"@id\":\"https:\\\/\\\/rakuha.com\\\/#person\"},\"image\":{\"@type\":\"ImageObject\",\"url\":\"https:\\\/\\\/i0.wp.com\\\/rakuha.com\\\/wp-content\\\/uploads\\\/2019\\\/05\\\/Screenshot_2019-05-26-rakuyou-1-PaizaCloud-Instant-Linux-with-Web-UI.png?fit=765%2C931&ssl=1\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?p=46\\\/#articleImage\",\"width\":765,\"height\":931},\"datePublished\":\"2019-05-27T23:17:10+09:00\",\"dateModified\":\"2019-06-01T06:52:07+09:00\",\"inLanguage\":\"ja\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/rakuha.com\\\/?p=46#webpage\"},\"isPartOf\":{\"@id\":\"https:\\\/\\\/rakuha.com\\\/?p=46#webpage\"},\"articleSection\":\"CTF, CTF, ctf4b, seccon\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?p=46#breadcrumblist\",\"itemListElement\":[{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/rakuha.com#listItem\",\"position\":1,\"name\":\"\\u30db\\u30fc\\u30e0\",\"item\":\"https:\\\/\\\/rakuha.com\",\"nextItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?cat=2#listItem\",\"name\":\"CTF\"}},{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?cat=2#listItem\",\"position\":2,\"name\":\"CTF\",\"item\":\"https:\\\/\\\/rakuha.com\\\/?cat=2\",\"nextItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?p=46#listItem\",\"name\":\"SECCON for Beginners CTF 2019 writeup\"},\"previousItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/rakuha.com#listItem\",\"name\":\"\\u30db\\u30fc\\u30e0\"}},{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?p=46#listItem\",\"position\":3,\"name\":\"SECCON for Beginners CTF 2019 writeup\",\"previousItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?cat=2#listItem\",\"name\":\"CTF\"}}]},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/#person\",\"name\":\"\\u3089\\u304f\\u306f\\u3002\",\"image\":{\"@type\":\"ImageObject\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?p=46#personImage\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/ca4d56d3c7da793753d47fb09627affdbd776d9d5809b90d52db58b0d60cbafd?s=96&d=mm&r=g\",\"width\":96,\"height\":96,\"caption\":\"\\u3089\\u304f\\u306f\\u3002\"}},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?author=1#author\",\"url\":\"https:\\\/\\\/rakuha.com\\\/?author=1\",\"name\":\"\\u3089\\u304f\\u306f\\u3002\",\"image\":{\"@type\":\"ImageObject\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?p=46#authorImage\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/ca4d56d3c7da793753d47fb09627affdbd776d9d5809b90d52db58b0d60cbafd?s=96&d=mm&r=g\",\"width\":96,\"height\":96,\"caption\":\"\\u3089\\u304f\\u306f\\u3002\"}},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/?p=46#webpage\",\"url\":\"https:\\\/\\\/rakuha.com\\\/?p=46\",\"name\":\"SECCON for Beginners CTF 2019 writeup | Rakuha's Blog\",\"inLanguage\":\"ja\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/rakuha.com\\\/#website\"},\"breadcrumb\":{\"@id\":\"https:\\\/\\\/rakuha.com\\\/?p=46#breadcrumblist\"},\"author\":{\"@id\":\"https:\\\/\\\/rakuha.com\\\/?author=1#author\"},\"creator\":{\"@id\":\"https:\\\/\\\/rakuha.com\\\/?author=1#author\"},\"datePublished\":\"2019-05-27T23:17:10+09:00\",\"dateModified\":\"2019-06-01T06:52:07+09:00\"},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/rakuha.com\\\/#website\",\"url\":\"https:\\\/\\\/rakuha.com\\\/\",\"name\":\"Rakuha's Blog\",\"description\":\"\\u60c5\\u5831\\u30bb\\u30ad\\u30e5\\u30ea\\u30c6\\u30a3\\u95a2\\u9023\\u306e\\u4e8b\\u3068\\u304b\",\"inLanguage\":\"ja\",\"publisher\":{\"@id\":\"https:\\\/\\\/rakuha.com\\\/#person\"}}]}\n\t\t<\/script>\n\t\t<!-- All in One SEO -->\n\n","aioseo_head_json":{"title":"SECCON for Beginners CTF 2019 writeup | Rakuha's Blog","description":"","canonical_url":"https:\/\/rakuha.com\/?p=46","robots":"max-image-preview:large","keywords":"ctf,ctf4b,seccon","webmasterTools":{"google-site-verification":"I_JXw338RMBFTetbO8o1Zw6x6zpg9_FAVU7TCeD1E-4","miscellaneous":""},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/rakuha.com\/?p=46#article","name":"SECCON for Beginners CTF 2019 writeup | Rakuha's Blog","headline":"SECCON for Beginners CTF 2019 writeup","author":{"@id":"https:\/\/rakuha.com\/?author=1#author"},"publisher":{"@id":"https:\/\/rakuha.com\/#person"},"image":{"@type":"ImageObject","url":"https:\/\/i0.wp.com\/rakuha.com\/wp-content\/uploads\/2019\/05\/Screenshot_2019-05-26-rakuyou-1-PaizaCloud-Instant-Linux-with-Web-UI.png?fit=765%2C931&ssl=1","@id":"https:\/\/rakuha.com\/?p=46\/#articleImage","width":765,"height":931},"datePublished":"2019-05-27T23:17:10+09:00","dateModified":"2019-06-01T06:52:07+09:00","inLanguage":"ja","mainEntityOfPage":{"@id":"https:\/\/rakuha.com\/?p=46#webpage"},"isPartOf":{"@id":"https:\/\/rakuha.com\/?p=46#webpage"},"articleSection":"CTF, CTF, ctf4b, seccon"},{"@type":"BreadcrumbList","@id":"https:\/\/rakuha.com\/?p=46#breadcrumblist","itemListElement":[{"@type":"ListItem","@id":"https:\/\/rakuha.com#listItem","position":1,"name":"\u30db\u30fc\u30e0","item":"https:\/\/rakuha.com","nextItem":{"@type":"ListItem","@id":"https:\/\/rakuha.com\/?cat=2#listItem","name":"CTF"}},{"@type":"ListItem","@id":"https:\/\/rakuha.com\/?cat=2#listItem","position":2,"name":"CTF","item":"https:\/\/rakuha.com\/?cat=2","nextItem":{"@type":"ListItem","@id":"https:\/\/rakuha.com\/?p=46#listItem","name":"SECCON for Beginners CTF 2019 writeup"},"previousItem":{"@type":"ListItem","@id":"https:\/\/rakuha.com#listItem","name":"\u30db\u30fc\u30e0"}},{"@type":"ListItem","@id":"https:\/\/rakuha.com\/?p=46#listItem","position":3,"name":"SECCON for Beginners CTF 2019 writeup","previousItem":{"@type":"ListItem","@id":"https:\/\/rakuha.com\/?cat=2#listItem","name":"CTF"}}]},{"@type":"Person","@id":"https:\/\/rakuha.com\/#person","name":"\u3089\u304f\u306f\u3002","image":{"@type":"ImageObject","@id":"https:\/\/rakuha.com\/?p=46#personImage","url":"https:\/\/secure.gravatar.com\/avatar\/ca4d56d3c7da793753d47fb09627affdbd776d9d5809b90d52db58b0d60cbafd?s=96&d=mm&r=g","width":96,"height":96,"caption":"\u3089\u304f\u306f\u3002"}},{"@type":"Person","@id":"https:\/\/rakuha.com\/?author=1#author","url":"https:\/\/rakuha.com\/?author=1","name":"\u3089\u304f\u306f\u3002","image":{"@type":"ImageObject","@id":"https:\/\/rakuha.com\/?p=46#authorImage","url":"https:\/\/secure.gravatar.com\/avatar\/ca4d56d3c7da793753d47fb09627affdbd776d9d5809b90d52db58b0d60cbafd?s=96&d=mm&r=g","width":96,"height":96,"caption":"\u3089\u304f\u306f\u3002"}},{"@type":"WebPage","@id":"https:\/\/rakuha.com\/?p=46#webpage","url":"https:\/\/rakuha.com\/?p=46","name":"SECCON for Beginners CTF 2019 writeup | Rakuha's Blog","inLanguage":"ja","isPartOf":{"@id":"https:\/\/rakuha.com\/#website"},"breadcrumb":{"@id":"https:\/\/rakuha.com\/?p=46#breadcrumblist"},"author":{"@id":"https:\/\/rakuha.com\/?author=1#author"},"creator":{"@id":"https:\/\/rakuha.com\/?author=1#author"},"datePublished":"2019-05-27T23:17:10+09:00","dateModified":"2019-06-01T06:52:07+09:00"},{"@type":"WebSite","@id":"https:\/\/rakuha.com\/#website","url":"https:\/\/rakuha.com\/","name":"Rakuha's Blog","description":"\u60c5\u5831\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u95a2\u9023\u306e\u4e8b\u3068\u304b","inLanguage":"ja","publisher":{"@id":"https:\/\/rakuha.com\/#person"}}]},"og:locale":"ja_JP","og:site_name":"Rakuha's Blog","og:type":"article","og:title":"SECCON for Beginners CTF 2019 writeup | Rakuha's Blog","og:url":"https:\/\/rakuha.com\/?p=46","og:image":"https:\/\/rakuha.com\/wp-content\/uploads\/2019\/05\/\u7d50\u679c.png","og:image:secure_url":"https:\/\/rakuha.com\/wp-content\/uploads\/2019\/05\/\u7d50\u679c.png","og:image:width":1193,"og:image:height":517,"article:published_time":"2019-05-27T14:17:10+00:00","article:modified_time":"2019-05-31T21:52:07+00:00","twitter:card":"summary","twitter:site":"@rakuha3","twitter:title":"SECCON for Beginners CTF 2019 writeup | Rakuha's Blog","twitter:image":"https:\/\/rakuha.com\/wp-content\/uploads\/2019\/05\/\u7d50\u679c.png"},"aioseo_meta_data":{"post_id":"46","title":null,"description":null,"keywords":null,"keyphrases":null,"primary_term":null,"canonical_url":null,"og_title":null,"og_description":null,"og_object_type":"default","og_image_type":"default","og_image_url":null,"og_image_width":null,"og_image_height":null,"og_image_custom_url":null,"og_image_custom_fields":null,"og_video":null,"og_custom_url":null,"og_article_section":null,"og_article_tags":null,"twitter_use_og":false,"twitter_card":"default","twitter_image_type":"default","twitter_image_url":null,"twitter_image_custom_url":null,"twitter_image_custom_fields":null,"twitter_title":null,"twitter_description":null,"schema":{"blockGraphs":[],"customGraphs":[],"default":{"data":{"Article":[],"Course":[],"Dataset":[],"FAQPage":[],"Movie":[],"Person":[],"Product":[],"ProductReview":[],"Car":[],"Recipe":[],"Service":[],"SoftwareApplication":[],"WebPage":[]},"graphName":"","isEnabled":true},"graphs":[],"defaultGraph":"","defaultPostTypeGraph":""},"schema_type":null,"schema_type_options":null,"pillar_content":false,"robots_default":true,"robots_noindex":false,"robots_noarchive":false,"robots_nosnippet":false,"robots_nofollow":false,"robots_noimageindex":false,"robots_noodp":false,"robots_notranslate":false,"robots_max_snippet":null,"robots_max_videopreview":null,"robots_max_imagepreview":"large","priority":null,"frequency":null,"local_seo":null,"breadcrumb_settings":null,"limit_modified_date":false,"ai":null,"created":"2020-12-25 14:01:36","updated":"2022-09-13 16:02:17","seo_analyzer_scan_date":null},"aioseo_breadcrumb":"<div class=\"aioseo-breadcrumbs\"><span class=\"aioseo-breadcrumb\">\n\t\t\t<a href=\"https:\/\/rakuha.com\" title=\"\u30db\u30fc\u30e0\">\u30db\u30fc\u30e0<\/a>\n\t\t<\/span><span class=\"aioseo-breadcrumb-separator\">&raquo;<\/span><span class=\"aioseo-breadcrumb\">\n\t\t\t<a href=\"https:\/\/rakuha.com\/?cat=2\" title=\"CTF\">CTF<\/a>\n\t\t<\/span><span class=\"aioseo-breadcrumb-separator\">&raquo;<\/span><span class=\"aioseo-breadcrumb\">\n\t\t\tSECCON for Beginners CTF 2019 writeup\n\t\t<\/span><\/div>","aioseo_breadcrumb_json":[{"label":"\u30db\u30fc\u30e0","link":"https:\/\/rakuha.com"},{"label":"CTF","link":"https:\/\/rakuha.com\/?cat=2"},{"label":"SECCON for Beginners CTF 2019 writeup","link":"https:\/\/rakuha.com\/?p=46"}],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/rakuha.com\/index.php?rest_route=\/wp\/v2\/posts\/46","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=46"}],"version-history":[{"count":12,"href":"https:\/\/rakuha.com\/index.php?rest_route=\/wp\/v2\/posts\/46\/revisions"}],"predecessor-version":[{"id":61,"href":"https:\/\/rakuha.com\/index.php?rest_route=\/wp\/v2\/posts\/46\/revisions\/61"}],"wp:attachment":[{"href":"https:\/\/rakuha.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=46"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rakuha.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=46"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rakuha.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=46"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}