vBulletin 5.x through 5.1.6 allows remote authenticated users to bypass authorization checks and inject private messages into conversations via vectors related to an input validation failure.Referenceshttp://www.vbulletin.com/forum/forum/vbulletin-announcements/vbulletin-announcements_aa/4319488-security-patch-released-for-vbulletin-5-1-4-5-1-6-and-vbulletin-cloudhttp://www.openwall.com/lists/oss-security/2015/04/24/4
