CVE-2021-26867: Windows Hyper-V Remote Code Execution Vulnerability

Overview

Severity

Critical (CVSS 9.9)

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C

Category

Remote Code Execution

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2021-Mar

Released

2021-03-09

EPSS Score

1.18% (percentile: 78.8%)

FAQ

Which Hyper-V systems are vulnerable? Any Hyper-V client which is configured to use the Plan 9 file system could be vulnerable. An authenticated attacker who successfully exploited this vulnerability on a Hyper-V client could cause code to execute on the Hyper-V server.

Affected Products (6)

Windows

• Windows 10 Version 1909 for x64-based Systems
• Windows Server, version 1909 (Server Core installation)
• Windows 10 Version 2004 for x64-based Systems
• Windows Server, version 2004 (Server Core installation)
• Windows 10 Version 20H2 for x64-based Systems
• Windows Server, version 20H2 (Server Core Installation)

Security Updates (2)

• 5000808
• 5000802

Acknowledgments

<a href="https://twitter.com/rezer0dai">@rezer0dai</a>

Revision History

• 2021-03-09: Information published.