Hyper-V RemoteFX vGPU Remote Code Execution Vulnerability

CVE-2020-1041
Security Vulnerability

Released: Jul 14, 2020

Assigning CNA
Microsoft
CVE.org link
CVE-2020-1041

Executive Summary

A remote code execution vulnerability exists when Hyper-V RemoteFX vGPU on a host server fails to properly validate input from an authenticated user on a guest operating system. To exploit the vulnerability, an attacker could run a specially crafted application on a guest operating system, attacking certain third-party video drivers running on the Hyper-V host. This could then cause the host operating system to execute arbitrary code.

An attacker who successfully exploited the vulnerability could execute arbitrary code on the host operating system.

There is no patch to fix this vulnerability, and the update listed will forcibly disable RemoteFX when applied. More information can be found in the FAQ below.

The software listed in the Security Updates table indicates those operating systems for which RemoteFX vGPU is currently available. RemoteFX vGPU has been deprecated in Windows Server 2019 and customers are advised to use Discrete Device Assignment (DDA) instead of RemoteFX vGPU. DDA was introduced in Windows Server 2016.

Exploitability

The following table provides an exploitability assessment for this vulnerability at the time of original publication.

Publicly disclosed
No
Exploited
No
Exploitability assessment
Exploitation Less Likely

FAQ

How do I know if I'm using RemoteFX?

Please review the information here to determine if you are using RemoteFX.

How can I protect my server from this vulnerability?

If you are running Windows Server 2016 or Windows Server 2019, we recommend you use Discrete Device Assignment (DDA) as opposed to RemoteFX vGPU to enable graphics virtualization. If you are running windows Server 2012 R2 or older, we recommend not using RemoteFX vGPU. Please see Plan for GPU acceleration in Windows Server for more information.

What steps should I take if RemoteFX is required in my environment?

Customers who require RemoteFX in their environment can review the information here.

Where can I find more information about the deprecation of RemoteFX?

  1. Features removed or planned for replacement starting Windows Server 2019
  2. Features removed or planned for replacement starting with Windows Server, version 1803

Why is Microsoft planning to disable and remove RemoteFX instead of fixing the vulnerability?

In October 2019, Microsoft announced that we were stopping development of Remote FX and building new functionality. For Windows 10 version 1809 and higher, and Windows Server 2019, RemoteFX vGPU is no longer supported or actively developed. Since these newly identified vulnerabilities are architectural in nature, and the feature is already deprecated on newer versions of Windows, Microsoft has determined that disabling and removing RemoteFX is a better course of action. Microsoft has developed a different platform that is inherently much more secure. Please see Plan for GPU acceleration in Windows Server for more information.

Acknowledgements

  • Discovered by Piotr Bania of Cisco Talos
Microsoft recognizes the efforts of those in the security community who help us protect customers through coordinated vulnerability disclosure. See Acknowledgements for more information.

Security Updates

To determine the support lifecycle for your software, see the Microsoft Support Lifecycle.

Release date Descending
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Disclaimer

The information provided in the Microsoft Knowledge Base is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

Revisions

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