CVE-2026-20870 - 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	Windows 11 24h2 Windows 11 25h2 Windows Server 2025

No data.

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References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20870

History

Tue, 13 Jan 2026 20:15:00 +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		Windows Win32 Kernel Subsystem Elevation of Privilege Vulnerability
First Time appeared		Microsoft Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows Server 2025
Weaknesses		CWE-416
CPEs		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_2025::::::::
Vendors & Products		Microsoft Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows Server 2025
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20870
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: 2026-01-13T17:56:59.544Z

Updated: 2026-01-13T19:09:28.406Z

Reserved: 2025-12-03T05:54:20.382Z

Link: CVE-2026-20870

Vulnrichment

Updated: 2026-01-13T19:09:23.904Z

NVD

Status : Received

Published: 2026-01-13T18:16:16.650

Modified: 2026-01-13T18:16:16.650

Link: CVE-2026-20870

Redhat

No data.

OpenCVE Enrichment

No data.

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