Cross-site scripting (XSS) vulnerability in vBulletin 3.6.10 and 3.7.1 allows remote attackers to inject arbitrary web script or HTML via unknown vectors and an "obscure method." NOTE: the vector is probably in the redirect parameter to the Admin Control Panel (admincp/index.php).
https://exchange.xforce.ibmcloud.com/vulnerabilities/43090
http://www.vbulletin.com/forum/showthread.php?t=274882
http://www.securitytracker.com/id?1020322
http://www.securityfocus.com/archive/1/493340/100/0/threaded