Cross-site scripting (XSS) vulnerability in vBulletin 3.7.2 PL1 and 3.6.10 PL3, when "Show New Private Message Notification Pop-Up" is enabled, allows remote authenticated users to inject arbitrary web script or HTML via a private message subject (aka newpm[title]).
https://exchange.xforce.ibmcloud.com/vulnerabilities/44576
http://www.vbulletin.com/forum/showthread.php?t=282133
http://www.securitytracker.com/id?1020727
http://www.securityfocus.com/bid/30777
http://www.coresecurity.com/content/vbulletin-cross-site-scripting-vulnerability
http://securityreason.com/securityalert/4182