classes/Filter/WhitelistedExternalFilter.php in the Authoring HTML module 6.x-1.x before 6.x-1.1 for Drupal does not properly validate sources with the host white list, which allows remote authenticated users to bypass intended access restrictions and conduct cross-site scripting (XSS) attacks.
https://exchange.xforce.ibmcloud.com/vulnerabilities/76127
http://www.openwall.com/lists/oss-security/2012/06/14/3
http://secunia.com/advisories/49387