Buffer overflow in WGagent in WatchGuard WSM and Fireware before 11.8 allows remote attackers to execute arbitrary code via a long sessionid value in a cookie.
http://www.kb.cert.org/vuls/id/233990
http://watchguardsecuritycenter.com/2013/10/17/xtm-11-8-secfixes/
http://watchguardsecuritycenter.com/2013/10/17/watchguard-dimension-and-fireware-xtm-11-8/