source: https://www.securityfocus.com/bid/16958/info

Easy Forum is prone to an HTML-injection vulnerability. This issue is due to a failure in the application 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 for the theft of cookie-based authentication credentials. An attacker could also exploit this issue to control how the site is rendered to the user; other attacks are also possible. 

This issue is reported to affect version 2.5. Other versions may also be vulnerable.

Example 'Image File' data sufficient to demonstrate this issue was provided:
javascript:alert(123) sometext.gif