CVE-2026-20920 - Vulnerability Details - OpenCVE

Use after free 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.

Exploitation none

Automatable no

Technical Impact total

Vendors	Products
Microsoft Subscribe	Windows 11 23h2 Subscribe Windows Server 2022 Subscribe Windows Server 23h2 Subscribe

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20920

History

Tue, 13 Jan 2026 19:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

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

Type	Values Removed	Values Added
Description		Use after free 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 Server 2022 Microsoft windows Server 23h2
Weaknesses		CWE-416
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_server_2022:::::::: cpe:2.3:o:microsoft:windows_server_23h2::::::::
Vendors & Products		Microsoft Microsoft windows 11 23h2 Microsoft windows Server 2022 Microsoft windows Server 23h2
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20920
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'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2026-01-13T17:56:38.801Z

Updated: 2026-01-13T19:10:45.721Z

Reserved: 2025-12-04T20:04:16.335Z

Link: CVE-2026-20920

Vulnrichment

Updated: 2026-01-13T19:10:40.019Z

NVD

Status : Received

Published: 2026-01-13T18:16:18.303

Modified: 2026-01-13T18:16:18.303

Link: CVE-2026-20920

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-416

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