The mc_issue_note_update function in the SOAP API in MantisBT before 1.2.11 does not properly check privileges, which allows remote attackers with bug reporting privileges to edit arbitrary bugnotes via a SOAP request.
https://exchange.xforce.ibmcloud.com/vulnerabilities/76180
http://www.securityfocus.com/bid/56467
http://www.securityfocus.com/bid/53907
http://www.openwall.com/lists/oss-security/2012/06/11/6
http://www.openwall.com/lists/oss-security/2012/06/09/1
http://www.mantisbt.org/bugs/view.php?id=14340
http://www.mantisbt.org/bugs/changelog_page.php?version_id=148
http://security.gentoo.org/glsa/glsa-201211-01.xml
http://secunia.com/advisories/51199
http://secunia.com/advisories/49414
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