OpenStack Identity (Keystone) Folsom 2012.2.4 and earlier, Grizzly before 2013.1.1, and Havana does not immediately revoke the authentication token when deleting a user through the Keystone v2 API, which allows remote authenticated users to retain access via the token.
OpenStack Keystone Essex 2012.1.3 and earlier, Folsom 2012.2.3 and earlier, and Grizzly grizzly-2 and earlier allows remote attackers to cause a denial of service (disk consumption) via many invalid token requests that trigger excessive generation of log entries.
OpenStack Keystone Grizzly before 2013.1, Folsom 2012.1.3 and earlier, and Essex does not properly check if the (1) user, (2) tenant, or (3) domain is enabled when using EC2-style authentication, which allows context-dependent attackers to bypass access restrictions.