XSS vulnerability in Zimplit CMS

Vulnerability ID: HTB22715
Reference: http://www.htbridge.ch/advisory/xss_vulnerability_in_zimplit_cms.html
Product: Zimplit CMS
Vendor: Zimplit ( http://www.zimplit.com/ )
Vulnerable Version: Current at 22.11.2010 and Probably Prior Versions
Vendor Notification: 22 November 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 "zimplit.php" script on "load" action to properly sanitize user-supplied input in "file" 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:

http://host/path/zimplit.php?action=load&file=%3Cscript%3Ealert%28document.cookie%29%3C/script%3E