The MITRE CVE dictionary describes this issue as:
The libvirt driver in OpenStack Compute (Nova) before 2013.2.2 and icehouse before icehouse-2 allows remote authenticated users to cause a denial of service (disk consumption) by creating and deleting instances with unique os_type settings, which triggers the creation of a new ephemeral disk backing file.
Find out more about CVE-2013-6437 from the
MITRE CVE dictionary dictionary and
Red Hat Product Security has rated this issue as having moderate security impact in Red Hat OpenStack Platform 3.0. This issue is not currently planned to be addressed in future updates. For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/.