XSS vulnerability in Contenido CMS

Vulnerability ID: HTB22636
Reference: http://www.htbridge.ch/advisory/xss_vulnerability_in_contenido_cms_1.html
Product: Contenido CMS
Vendor: four for business AG ( http://www.contenido.org/ )
Vulnerable Version: 4.8.12 and Probably Prior Versions
Vendor Notification: 29 September 2010
Vulnerability Type: XSS (Cross Site Scripting)
Status: Fixed by Vendor
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 "front_content.php" script to properly sanitize user-supplied input in "idart" 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/en/front_content.php?idart=1267%27%22%3E%3Cscript%3Ealert%28document.cookie%29%3C/script%3E

Solution: Upgrade to the most recent version