The MySQL token driver in OpenStack Identity (Keystone) 2014.1.x before 2014.1.2.1 and Juno before Juno-3 stores timestamps with the incorrect precision, which causes the expiration comparison for tokens to fail and allows remote authenticated users to retain access via an expired token.
https://bugs.launchpad.net/keystone/+bug/1347961
http://www.ubuntu.com/usn/USN-2324-1
http://www.openwall.com/lists/oss-security/2014/08/15/6