source: http://www.securityfocus.com/bid/31908/info

Adam Wright HTMLTidy is prone to a cross-site scripting vulnerability because it fails to properly sanitize user-supplied input.

An attacker may leverage this issue to execute arbitrary script code in the browser of an unsuspecting user in the context of the affected site. This may let the attacker steal cookie-based authentication credentials and launch other attacks.

HTMLTidy 0.5 is vulnerable; other versions may also be affected. Products that include HTMLTidy as a component will also be vulnerable.

NOTE: This record was previously titled 'Kayako eSupport html-tidy-logic.php Cross Site Scripting Vulnerability'. It has been updated to properly describe the vulnerability as an HTMLTidy issue. 

http://www.example.com/[script_dir]/includes/htmlArea/plugins/HtmlTidy/html-tidy-logic.php?jsMakeSrc=return%20ns;%20}%20alert(2008);%20function%20whynot(){%20alert(2);