Remote Code Execution Flaw in Windows Hyper-V
CVE-2026-21247

7.3HIGH

Key Information:

Vendor

Microsoft
Status
Windows 10 Version 1607
Windows 10 Version 1809
Windows 10 Version 21h2
Windows 10 Version 22h2
Vendor
CVE Published:
10 February 2026

What is CVE-2026-21247?

An improper input validation vulnerability in Windows Hyper-V allows an authorized attacker to execute arbitrary code locally. This flaw enables attackers to potentially compromise system integrity and gain unauthorized access to sensitive data. Users of Windows Hyper-V should apply the latest updates to mitigate this security risk.

Affected Version(s)

Windows 10 Version 1607 x64-based Systems 10.0.14393.0 < 10.0.14393.8868

Windows 10 Version 1809 x64-based Systems 10.0.17763.0 < 10.0.17763.8389

Windows 10 Version 21H2 x64-based Systems 10.0.19044.0 < 10.0.19044.6937

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE...
vendor-advisorypatch

CVSS V3.1

Score:
7.3
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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