tunnelform.yaws in Nortel SSL VPN 4.2.1.6 allows remote attackers to execute arbitrary commands via a link in the a parameter, which is executed with extra privileges in a cryptographically signed Java Applet.
http://www.vupen.com/english/advisories/2005/2845
http://www.securityfocus.com/archive/1/419263/100/0/threaded