Privilege Elevation Vulnerability in Windows Win32K by Microsoft
CVE-2026-20863

7HIGH

Key Information:

Vendor

Microsoft
Status
Windows Server 2022
Windows Server 2025 (server Core Installation)
Windows 11 Version 25h2
Windows 11 Version 22h3
Vendor
CVE Published:
13 January 2026

What is CVE-2026-20863?

A double free vulnerability exists in the Windows Win32K component, which allows an authorized attacker to execute a local privilege escalation attack. By exploiting this flaw, the attacker can gain higher privileges than intended, potentially compromising system integrity and security. Timely updates and patches are essential to mitigate risks associated with this vulnerability to maintain a secure environment.

Affected Version(s)

Windows 11 version 22H3 ARM64-based Systems 10.0.22631.0 < 10.0.22631.6491

Windows 11 Version 23H2 x64-based Systems 10.0.22631.0 < 10.0.22631.6491

Windows 11 Version 24H2 ARM64-based Systems 10.0.26100.0 < 10.0.26100.7623

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

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