Elevation of Privileges in Windows Subsystem for Linux by Microsoft
CVE-2026-21242

7HIGH

Key Information:

Vendor

Microsoft
Status
Windows 10 Version 21h2
Windows 10 Version 22h2
Windows 11 Version 22h3
Windows 11 Version 23h2
Vendor
CVE Published:
10 February 2026

What is CVE-2026-21242?

A vulnerability in the Windows Subsystem for Linux enables an attacker with local access to exploit a use after free flaw, potentially allowing for unauthorized escalation of privileges. This issue can lead to significant security risks if not addressed promptly, so implementing the latest patches is essential to maintain system integrity.

Affected Version(s)

Windows 10 Version 21H2 ARM64-based Systems 10.0.19044.0 < 10.0.19044.6937

Windows 10 Version 22H2 ARM64-based Systems 10.0.19045.0 < 10.0.19045.6937

Windows 11 version 22H3 ARM64-based Systems 10.0.22631.0 < 10.0.22631.6649

References

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

CVSS V3.1

Score:
7
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
High
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.