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. Per http://www.ubuntu.com/usn/USN-1715-1/
A security issue affects these releases of Ubuntu and its derivatives:
Ubuntu 12.10 Ubuntu 12.04 LTS
Publication date: Mon, 25 Feb 2013 01:55:00 +0000