Cross-site scripting (XSS) vulnerability in knowledgebase.php in WHMCompleteSolution 2.1 and earlier allows remote attackers to inject arbitrary web script or HTML via the search parameters.
http://www.vupen.com/english/advisories/2005/2883
http://www.securityfocus.com/bid/15856
http://secunia.com/advisories/18029
http://pridels0.blogspot.com/2005/12/whmcompletesolution-xss-vuln.html