Cross-site request forgery (CSRF) vulnerability in Citrix Presentation Server 4.0 and 4.5, MetaFrame Presentation Server 3.0, and Access Essentials 1.0 through 2.0 allows remote attackers to execute arbitrary published applications, and possibly other programs, as authenticated users via the InitialProgram key in an ICA connection. NOTE: some of these details are obtained from third party information.
http://www.vupen.com/english/advisories/2007/3870
http://www.securitytracker.com/id?1018962
http://www.securityfocus.com/bid/26451
http://www.gnucitizen.org/blog/citrix-owning-the-legitimate-backdoor/
http://support.citrix.com/article/CTX115245
http://secunia.com/advisories/27633
http://packetstormsecurity.org/0210-exploits/hackingcitrix.txt