Cross-site scripting (XSS) vulnerability in the mycode_parse_video function in inc/class_parser.php in MyBB (aka MyBulletinBoard) before 1.6.12 allows remote attackers to inject arbitrary web script or HTML via vectors related to Yahoo video URLs.
https://github.com/mybb/mybb/commit/238696e37d6a22b89e6bba11e4de3e6620cb5547
http://www.securityfocus.com/bid/64570
http://secunia.com/advisories/55945
http://osvdb.org/show/osvdb/101544
http://blog.mybb.com/2013/12/16/mybb-1-6-12-released-security-maintenance-release