A flaw was found in OpenStack Keystone. This vulnerability allows remote authenticated users to bypass intended authorization restrictions. This occurs because OpenStack Keystone does not properly handle EC2 (Elastic Compute Cloud) tokens when a user's role has been removed from a tenant. An attacker can leverage a token associated with a removed user role to gain unauthorized access.
https://github.com/openstack/keystone/commit/9d68b40cb9ea818c48152e6c712ff41586ad9653
https://github.com/openstack/keystone/commit/8735009dc5b895db265a1cd573f39f4acfca2a19
https://github.com/openstack/keystone/commit/37308dd4f3e33f7bd0f71d83fd51734d1870713b
https://exchange.xforce.ibmcloud.com/vulnerabilities/80333
https://bugs.launchpad.net/keystone/+bug/1064914
https://access.redhat.com/security/cve/CVE-2012-5571
http://www.ubuntu.com/usn/USN-1641-1
http://www.securityfocus.com/bid/56726
http://www.openwall.com/lists/oss-security/2012/11/28/6
http://www.openwall.com/lists/oss-security/2012/11/28/5
http://secunia.com/advisories/51436
http://secunia.com/advisories/51423
http://rhn.redhat.com/errata/RHSA-2012-1557.html
http://rhn.redhat.com/errata/RHSA-2012-1556.html
http://lists.fedoraproject.org/pipermail/package-announce/2012-December/094286.html