source: https://www.securityfocus.com/bid/52184/info

OSQA's CMS is prone to multiple HTML-injection vulnerabilities because it fails to sufficiently sanitize user-supplied data.

Attacker-supplied HTML or JavaScript code could run in the context of the affected site, potentially allowing the attacker to steal cookie-based authentication credentials and control how the site is rendered to the user; other attacks are also possible.

OSQA 3b is vulnerable; other versions may also be affected. 

http://www.example.com/questions/ask/ press url bar & put xss code <img src="<img src=search"/onerror=alert("xss")//">
http://www.example.com/questions/ask/ press picture bar & put xss code <img src="<img src=search"/onerror=alert("xss")//">