Citrix XenServer Multiple Security Updates

  • CTX134708
  • Created onSep 05, 2012
  • Updated onOct 08, 2014
Security Bulletin Severity High

Description of Problem

A number of security vulnerabilities have been identified in Citrix XenServer. These vulnerabilities affect all currently supported versions of Citrix XenServer up to and including version 6.0.2.

The following denial of service and guest-to-host privilege escalation vulnerabilities have been addressed:

    • hypercall physdev_get_free_pirq vulnerability (CVE-2012-3495)

    • PHYSDEVOP_map_pirq index vulnerability (CVE-2012-3498)

    • Qemu VT100 emulation vulnerability (CVE-2012-3515)

    • Grant table entry swaps have inadequate bounds checking (CVE-2012-3516)

    • HVM guest user mode MMIO emulation DoS vulnerability (CVE-2012-3432)

    • HVM guest destroy p2m teardown host DoS vulnerability (CVE-2012-3433)

    • hypercall set_debugreg vulnerability (CVE-2012-3494)

    • XENMEM_populate_physmap DoS vulnerability (CVE-2012-3496)

    • PV guest console vulnerability (CVE-2012-4606)

What Customers Should Do

Hotfixes have been released to address these issues in all supported versions and update levels of Citrix XenServer. Citrix strongly recommends that customers using Citrix XenServer identify and apply the hotfixes that relate to their deployed versions:

Citrix XenServer 6.0.2:

Citrix XenServer 6.0.0:

Citrix XenServer 5.6 Service Pack 2:

Citrix XenServer 5.6 Feature Pack 1:

Citrix XenServer 5.6:

Citrix XenServer 5.5 Update 2:

Citrix XenServer 5.0 Update 3:

Customers using Citrix XenServer 5.6 in the Common Criteria evaluated configuration should apply the following hotfix:


Citrix thanks James Forshaw of Context IS ( for working with us to protect Citrix customers.

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

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

Reporting Security Vulnerabilities to Citrix

Citrix welcomes input regarding the security of its products and considers any and all potential vulnerabilities seriously. If you would like to report a security issue to Citrix, please compose an e-mail to stating the exact version of the product in which the vulnerability was found and the steps needed to reproduce the vulnerability.

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