source: http://www.securityfocus.com/bid/30642/info

Kayako SupportSuite is prone to multiple input-validation vulnerabilities, including an SQL-injection issue, multiple cross-site scripting issues, and an HTML-injection issue. The vulnerabilities occur because the application fails to sufficiently sanitize user-supplied data.

Exploiting these issues could allow an attacker to steal cookie-based authentication credentials, control how the site is rendered to the user, compromise the application, access or modify data, or exploit latent vulnerabilities in the underlying database.

Versions prior to Kayako SupportSuite 3.30 are vulnerable. 

http://www.example.com/visitor/index.php?_m=livesupport&_a=startclientchat&sessionid="%20onload%3dalert(document.cookie)%20style=%3d