Cross-site request forgery (CSRF) vulnerability in Request Tracker (RT) 3.8.12 and other versions before 3.8.15, and 4.0.6 and other versions before 4.0.8, allows remote attackers to hijack the authentication of users for requests that toggle ticket bookmarks.
http://lists.bestpractical.com/pipermail/rt-announce/2012-October/000212.html