Launchpad.net

CVE 2013-2096

OpenStack Compute (Nova) Folsom, Grizzly, and Havana does not verify the virtual size of a QCOW2 image, which allows local users to cause a denial of service (host file system disk consumption) by creating an image with a large virtual size that does not contain a large amount of data.

See the CVE page on Mitre.org for more details.