Vulmon
Description of Problem
A number of security vulnerabilities have been identified in Citrix XenServer that may allow a malicious administrator of a PV guest VM to compromise or crash the host.
These vulnerabilities affect all currently supported versions of Citrix XenServer up to and including Citrix XenServer 7.0.
The following vulnerabilities have been addressed:
- CVE-2016-6258 (High): x86: Privilege escalation from PV guests
- CVE-2016-6259 (Medium): x86: Missing SMAP whitelisting in 32-bit exception / event delivery
Mitigating Factors
Only deployments with untrusted PV guests are at risk from these issues. Note that Microsoft Windows guests are not PV guests.
What Customers Should Do
Hotfixes have been released to address these issues. Citrix strongly recommends that affected customers install these hotfixes, which can be downloaded from the following locations:
Citrix XenServer 7.0: CTX214992 – https://support.citrix.com/article/CTX214992
Citrix XenServer 6.5 SP1: CTX214991 – https://support.citrix.com/article/CTX214991
Citrix XenServer 6.2 SP1: CTX214990 – https://support.citrix.com/article/CTX214990
Citrix XenServer 6.1: CTX214989 – https://support.citrix.com/article/CTX214989
Citrix XenServer 6.0.2: CTX214987 – https://support.citrix.com/article/CTX214987
Citrix XenServer 6.0.2 Common Criteria: CTX214988 – https://support.citrix.com/article/CTX214988
Citrix XenServer 6.0: CTX214986 – https://support.citrix.com/article/CTX214986
What Citrix Is Doing
Citrix is notifying customers and channel partners about this potential security issue. This article is also available from the Citrix Knowledge Center at http://support.citrix.com/.
Obtaining Support on This Issue
If you require technical assistance with this issue, please contact Citrix Technical Support. Contact details for Citrix Technical Support are available at https://www.citrix.com/support/open-a-support-case.html.
Reporting Security Vulnerabilities
Citrix welcomes input regarding the security of its products and considers any and all potential vulnerabilities seriously. For guidance on how to report security-related issues to Citrix, please see the following document: CTX081743 – Reporting Security Issues to Citrix
Changelog
| Date | Change |
|---|---|
| July 26th 2016 | Initial bulletin publishing |
| July 29th 2016 | Update to link in What Customers Should Do section |