CVE 2014-5252
The V3 API in OpenStack Identity (Keystone) 2014.1.x before 2014.1.2.1 and Juno before Juno-3 updates the issued_at value for UUID v2 tokens, which allows remote authenticated users to bypass the token expiration and retain access via a verification (1) GET or (2) HEAD request to v3/auth/tokens/.
See the 
CVE page on Mitre.org
for more details.
