CVE-2026-20811 - Vulnerability Details - OpenCVE

Access of resource using incompatible type ('type confusion') in Windows Win32K - ICOMP allows an authorized attacker to elevate privileges locally.

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Vendors	Products
Microsoft	Windows 11 23h2 Windows 11 24h2 Windows 11 25h2 Windows Server 2022 Windows Server 2025 Windows Server 23h2

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References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20811

History

Tue, 13 Jan 2026 18:15:00 +0000

Type	Values Removed	Values Added
Description		Access of resource using incompatible type ('type confusion') in Windows Win32K - ICOMP allows an authorized attacker to elevate privileges locally.
Title		Win32k Elevation of Privilege Vulnerability
First Time appeared		Microsoft Microsoft windows 11 23h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows Server 2022 Microsoft windows Server 2025 Microsoft windows Server 23h2
Weaknesses		CWE-822 CWE-843
CPEs		cpe:2.3:o:microsoft:windows_11_23H2:::::::arm64:* cpe:2.3:o:microsoft:windows_11_23H2:::::::x64:* cpe:2.3:o:microsoft:windows_11_24H2:::::::arm64:* cpe:2.3:o:microsoft:windows_11_25H2:::::::arm64:* cpe:2.3:o:microsoft:windows_server_2022:::::::: cpe:2.3:o:microsoft:windows_server_2025:::::::: cpe:2.3:o:microsoft:windows_server_23h2::::::::
Vendors & Products		Microsoft Microsoft windows 11 23h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows Server 2022 Microsoft windows Server 2025 Microsoft windows Server 23h2
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20811
Metrics		cvssV3_1 `{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C'}`

MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2026-01-13T17:56:11.009Z

Updated: 2026-01-13T18:03:57.604Z

Reserved: 2025-12-03T05:54:20.372Z

Link: CVE-2026-20811

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-01-13T18:16:07.727

Modified: 2026-01-13T18:16:07.727

Link: CVE-2026-20811

Redhat

No data.

OpenCVE Enrichment

No data.

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