OpenStack Identity (Keystone) before 2013.2.4, 2014.1 before 2014.1.2, and Juno before Juno-2 does not properly handle chained delegation, which allows remote authenticated users to gain privileges by leveraging a (1) trust or (2) OAuth token with impersonation enabled to create a new token with additional roles.
http://www.securityfocus.com/bid/68026
http://www.openwall.com/lists/oss-security/2014/06/12/3
http://secunia.com/advisories/59547
http://secunia.com/advisories/57886
http://lists.opensuse.org/opensuse-security-announce/2014-06/msg00031.html