bug_actiongroup.php in MantisBT before 1.2.9 does not properly check the report_bug_threshold permission of the receiving project when moving a bug report, which allows remote authenticated users with the report_bug_threshold and move_bug_threshold privileges for a project to bypass intended access restrictions and move bug reports to a different project.
http://www.securityfocus.com/bid/52313
http://www.openwall.com/lists/oss-security/2012/03/06/9
http://www.mantisbt.org/bugs/view.php?id=13748
http://www.mantisbt.org/bugs/changelog_page.php?version_id=140
http://www.debian.org/security/2012/dsa-2500
http://security.gentoo.org/glsa/glsa-201211-01.xml
http://secunia.com/advisories/51199
http://secunia.com/advisories/49572
http://secunia.com/advisories/48258
http://lists.fedoraproject.org/pipermail/package-announce/2012-November/093064.html
http://lists.fedoraproject.org/pipermail/package-announce/2012-November/093063.html
http://lists.fedoraproject.org/pipermail/package-announce/2012-November/092926.html