Mozilla Firefox 4.x through 11.0, Thunderbird 5.0 through 11.0, and SeaMonkey before 2.9 do not properly construct the Origin and Sec-WebSocket-Origin HTTP headers, which might allow remote attackers to bypass an IPv6 literal ACL via a cross-site (1) XMLHttpRequest or (2) WebSocket operation involving a nonstandard port number and an IPv6 address that contains certain zero fields.
secunia.com/advisories/48972
secunia.com/advisories/49047
secunia.com/advisories/49055
www.mozilla.org/security/announce/2012/mfsa2012-28.html
www.securityfocus.com/bid/53230
bugzilla.mozilla.org/show_bug.cgi?id=694576
exchange.xforce.ibmcloud.com/vulnerabilities/75153
oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A16279