CVE-2021-34535: Remote Desktop Client Remote Code Execution Vulnerability

Overview

Severity
High (CVSS 8.8)
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C
Category
Remote Code Execution
Exploit Status
Not Exploited
Exploitation Likelihood
More Likely
Patch Tuesday
2021-Aug
Released
2021-08-10
Last Updated
2021-08-10
EPSS Score
21.69% (percentile: 97.5%)

FAQ

How could an attacker exploit this vulnerability? In the case of a Remote Desktop connection, an attacker with control of a Remote Desktop Server could trigger a remote code execution (RCE) on the machine when a victim connects to the attacking server with the vulnerable Remote Desktop Client. In the case of Hyper-V, a malicious program running in a guest VM could trigger guest-to-host RCE by exploiting this vulnerability in the Hyper-V Viewer when a victim running on the host connects to the attacking Hyper-V guest.

Affected Products (29)

Windows

  • Windows 10 Version 1809 for 32-bit Systems
  • Windows 10 Version 1809 for x64-based Systems
  • Windows 10 Version 1809 for ARM64-based Systems
  • Windows Server 2019
  • Windows 10 Version 1909 for 32-bit Systems
  • Windows 10 Version 1909 for x64-based Systems
  • Windows 10 Version 1909 for ARM64-based Systems
  • Remote Desktop client for Windows Desktop
  • Windows 10 Version 21H1 for x64-based Systems
  • Windows 10 Version 21H1 for ARM64-based Systems
  • Windows 10 Version 21H1 for 32-bit Systems
  • Windows 10 Version 2004 for 32-bit Systems
  • Windows 10 Version 2004 for ARM64-based Systems
  • Windows 10 Version 2004 for x64-based Systems
  • Windows 10 Version 20H2 for 32-bit Systems
  • Windows 10 Version 20H2 for ARM64-based Systems
  • Windows 10 for 32-bit Systems
  • Windows 10 for x64-based Systems
  • Windows 10 Version 1607 for 32-bit Systems
  • Windows 10 Version 1607 for x64-based Systems
  • Windows Server 2016
  • Windows 8.1 for 32-bit systems
  • Windows 8.1 for x64-based systems
  • Windows RT 8.1

ESU

  • Windows 7 for 32-bit Systems Service Pack 1
  • Windows 7 for x64-based Systems Service Pack 1
  • Windows Server 2008 R2 for x64-based Systems Service Pack 1
  • Windows Server 2012
  • Windows Server 2012 R2

Security Updates (12)

Acknowledgments

Malcolm Stagg

Revision History

  • 2021-08-10: Information published.
  • 2021-08-10: Updated links to security updates. This is an informational change only.