Multiple cross-site request forgery (CSRF) vulnerabilities in Movable Type before 4.38, 5.0x before 5.07, and 5.1x before 5.13 allow remote attackers to hijack the authentication of arbitrary users for requests that modify data via the (1) commenting feature or (2) community script.
http://www.securitytracker.com/id?1026738
http://www.securityfocus.com/bid/52138
http://www.movabletype.org/documentation/appendices/release-notes/513.html
http://www.movabletype.org/2012/02/movable_type_513_507_and_438_security_updates.html
http://www.debian.org/security/2012/dsa-2423