XSS vulnerability in Expression CMS

[advisory () htbridge ch]

Vulnerability ID: HTB22617
Reference: http://www.htbridge.ch/advisory/xss_vulnerability_in_expression_cms.html
Product: Expression 
Vendor: Backbone Technology ( http://www.backbonetechnology.com ) 
Vulnerable Version: Current at 18.09.2010 and Probably Prior Versions
Vendor Notification: 22 September 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 "contact us" page to properly sanitize user-supplied input in 
"section_id" 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/?section_id=1002815%27%22%3E%3Cscript%3Ealert%28/XSS/%29%3C/script%3E