Thierry Carrez (thierry) reports: Title: Denial of Service using XML entities in Nova/Cinder extensions Reporter: Grant Murphy (Red Hat) Products: Nova, Cinder Affects: Grizzly and later Description: Grant Murphy from Red Hat reported that vulnerabilities in XML request parsers were not fully patched in OSSA 2013-004. By leveraging XML entity expansion in specific extensions, an unauthenticated attacker may still consume excessive resources on the Nova or Cinder API servers, resulting in a denial of service and potentially a crash. Only Nova setups making use of the security group extension in Grizzly are affected. Only Cinder setups making use of the backups or volume transfer API extension in Grizzly are affected. Proposed patches: See attached patches. Unless a flaw is discovered in them, these patches will be merged to Nova & Cinder master (havana) and stable/grizzly branches on the public disclosure date. Please note that this was originally assigned a single CVE. It has since been split into two CVE's (CVE-2013-4179 continues to be used for Nova and CVE-2013-4202 should be used for Cinder).
Created attachment 782217 [details] cinder-grizzly-CVE-2013-4202.patch
Created attachment 782218 [details] cinder-master-CVE-2013-4202.patch
Created openstack-cinder tracking bugs for this issue: Affects: fedora-all [bug 995183] Affects: epel-6 [bug 995184]
Acknowledgements: This issue was discovered by Grant Murphy of the Red Hat Product Security Team.
This issue has been addressed in following products: OpenStack 3 for RHEL 6 Via RHSA-2013:1198 https://rhn.redhat.com/errata/RHSA-2013-1198.html