CVE-2026-20859 - Vulnerability Details - OpenCVE

Use after free in Windows Kernel-Mode Drivers 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 24h2 Windows 11 25h2 Windows Server 2025

No data.

No data.

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References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20859

History

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

Type	Values Removed	Values Added
Description		Use after free in Windows Kernel-Mode Drivers allows an authorized attacker to elevate privileges locally.
Title		Windows Kernel-Mode Driver 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-2026-20859
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: 2026-01-13T17:56:32.574Z

Updated: 2026-01-13T18:04:18.376Z

Reserved: 2025-12-03T05:54:20.380Z

Link: CVE-2026-20859

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-01-13T18:16:14.810

Modified: 2026-01-13T18:16:14.810

Link: CVE-2026-20859

Redhat

No data.

OpenCVE Enrichment

No data.

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