Mantis before 1.1.3 does not unset the session cookie during logout, which makes it easier for remote attackers to hijack sessions.
secunia.com/advisories/32975
www.gentoo.org/security/en/glsa/glsa-200812-07.xml
www.mantisbt.org/bugs/changelog_page.php
www.mantisbt.org/bugs/file_download.php?file_id=1988&type=bug
www.mantisbt.org/bugs/view.php?id=9664
www.openwall.com/lists/oss-security/2008/10/20/1
exchange.xforce.ibmcloud.com/vulnerabilities/46084