The Secure Gateway service in Citrix Secure Gateway 3.1 and earlier allows remote attackers to cause a denial of service (CPU consumption) via an unspecified request.
https://exchange.xforce.ibmcloud.com/vulnerabilities/51216
http://www.vupen.com/english/advisories/2009/1633
http://www.securitytracker.com/id?1022420
http://www.securityfocus.com/bid/35421