IBM Support

Security Bulletin: IBM SmartCloud Orchestrator - Nova compute DoS through ephemeral disk backing files (CVE-2013-6437)

Security Bulletin


By repeatedly creating snapshots, changing the os_type to a new random value, and
spawning new instances from the snapshot (and quickly deleting those instances), an authenticated user might generate lots of different ephemeral disk backing files. These files than fill up compute node disks, which potentially results in a Denial of Service against a Nova setup. Only Nova setups running the libvirt driver are affected.

Vulnerability Details

CVE ID: CVE-2013-6437
OpenStack Compute (Nova) is vulnerable to a denial of service, which is caused by an error when handling an image that has os_type metadata. By creating a snapshot of instance and deleting the original instance, an attacker might exploit this vulnerability to fill the disk and cause the system to crash.

CVSS Base Score: 5.0
CVSS Temporal Score See for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:L/Au:S/C:N/I:N/A:P)

Affected Products and Versions

IBM SmartCloud Orchestrator V2.2 and 2.3


The recommended solution is to upgrade to IBM SmartCloud Orchestrator Version 2.3.0 Fix Pack 1 as soon as practical.

Workarounds and Mitigations

The exposure applies only to KVM regions.
Ensure that IBM SmartCloud Orchestrator end users do not have access to the compute nodes

Get Notified about Future Security Bulletins


Complete CVSS v2 Guide
On-line Calculator v2

Related information

IBM Secure Engineering Web Portal
IBM Product Security Incident Response Blog



Change History

March 31st 2014 Original Copy Published

*The CVSS Environment Score is customer environment specific and will ultimately impact the Overall CVSS Score. Customers can evaluate the impact of this vulnerability in their environments by accessing the links in the Reference section of this Security Bulletin.


According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES "AS IS" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY.

Document information

More support for: IBM Cloud Orchestrator

Software version: 2.2,, 2.3

Operating system(s): Linux

Reference #: 1667330

Modified date: 11 February 2015