Description of Problem
A number of security vulnerabilities have been identified in Citrix XenServer that may allow a malicious administrator of a guest VM (depending on configuration) or an attacker on the management network to compromise 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-2016-3710/ CVE-2016-3712 (High): QEMU: Banked access to VGA memory uses inconsistent bounds checks
- CVE-2016-2107/ CVE-2016-2108 (Medium): MITM attacker can use a padding oracle attack to decrypt traffic
Mitigating Factors
Only deployments with HVM guests using an std-vga graphics device are at risk from the guest administrator attacker vulnerability.
XenServer 7.0 deployments are not at risk from the guest administrator attacker vulnerability.
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: CTX213770 - https://support.citrix.com/article/CTX213770
Citrix XenServer 6.5 SP1: CTX212747 – https://support.citrix.com/article/CTX212747 and CTX212858 – https://support.citrix.com/article/CTX212858
Citrix XenServer 6.2 SP1: CTX212746 – https://support.citrix.com/article/CTX212746
Citrix XenServer 6.1: CTX212745 – https://support.citrix.com/article/CTX212745
Citrix XenServer 6.0.2: CTX212743 – https://support.citrix.com/article/CTX212743
Citrix XenServer 6.0.2 Common Criteria: CTX212744 – https://support.citrix.com/article/CTX212744
Citrix XenServer 6.0: CTX212742 – https://support.citrix.com/article/CTX212742
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 |
---|---|
May 18th 2016 | Initial bulletin publishing |
June 16th 2016 | Added XenServer 7.0 details |