source: https://www.securityfocus.com/bid/16799/info

PHPX is prone to an HTML-injection vulnerability. The application fails to properly sanitize user-supplied input before using it in dynamically generated content. 

Attacker-supplied HTML and script code would be executed in the context of the affected website, potentially allowing an attacker to steal cookie-based authentication credentials or to control how the site is rendered to the user; other attacks are also possible.

PHPX version 3.5.9 is vulnerable; other versions may also be affected.

An example has been provided:

url=javascript:[code]]text[/url]