source: http://www.securityfocus.com/bid/40600/info

JForum is prone to multiple HTML-injection vulnerabilities because it fails to properly sanitize user-supplied input before using it in dynamically generated content.

Successful exploits will allow attacker-supplied HTML and script code to run in the context of the affected browser, potentially allowing the attacker to steal cookie-based authentication credentials or to control how the site is rendered to the user. Other attacks are also possible.

JForum 2.1.8 is vulnerable; other versions may also be affected. 

https://www.example.com/forum/bookmarks/insert/2/1.page?action=insertSave&description=<XSS>&module=bookmarks&relation_id=1&relation_type=2&title=<XSS>&visible=1