Citrix Hypervisor Security Update for CVE-2023-39368 and CVE-2023-38575

Description of Problem

Intel has disclosed several security issues affecting certain Intel CPUs. Although these are not vulnerabilities in the Citrix Hypervisor product itself, for the convenience of our customers we are providing a hotfix that includes updated Intel microcode to mitigate these CPU hardware issues.
These issues include the following identifiers:

• CVE-2023-39368
• CVE-2023-38575

In addition, Intel has disclosed an issue (CVE-2023-28746) that affects certain Intel CPUs, none of which are on the Citrix Hypervisor Hardware Compatibility List. However, it was not currently possible for guest VMs to determine if they were running on hardware that was vulnerable to this issue; the provided hotfix allows guest VMs that are running on unaffected CPUs to determine this, avoiding the possibility that they would display erroneous warning notifications.

What Customers Should Do

We have released a hotfix to address these issues. We recommend that customers install this hotfix and follow the instructions in the linked article as their update schedule permits. The hotfix can be downloaded from the following location:

CTX586659 - <https://support.citrix.com/article/CTX586659&gt;

What We Are Doing

We are notifying customers and channel partners about this potential security issue through the publication of this security bulletin on the Citrix Knowledge Center at <https://support.citrix.com/securitybulletins&gt;.

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.

Subscribe to Receive Alerts

We strongly recommend that all customers subscribe to receive alerts when a security bulletin is created or modified at <https://support.citrix.com/user/alerts&gt;.

Reporting Security Vulnerabilities to Us

We welcome input regarding the security of our products and consider any and all potential vulnerabilities seriously. For details on our vulnerability response process and guidance on how to report security-related issues to us, please see the following webpage: <https://www.citrix.com/about/trust-center/vulnerability-process.html&gt;.

Disclaimer

This document is provided on an “as is” basis and does not imply any kind of guarantee or warranty, including the warranties of merchantability or fitness for a particular use. Your use of the information on the document is at your own risk. Citrix reserves the right to change or update this document at any time. Customers are therefore recommended to always view the latest version of this document directly from the Citrix Knowledge Center.

Changelog