Moodle through 2.6.11, 2.7.x before 2.7.11, 2.8.x before 2.8.9, and 2.9.x before 2.9.3 does not properly restrict the availability of Flowplayer, which allows remote attackers to conduct cross-site scripting (XSS) attacks via a crafted .swf file.
https://moodle.org/mod/forum/discuss.php?d=323232
http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-48085