CVE-2026-21245 - Vulnerability Details - OpenCVE

Heap-based buffer overflow in Windows Kernel 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 11 26h1 Windows Server 2025

No data.

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References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21245

History

Tue, 10 Feb 2026 18:15:00 +0000

Type	Values Removed	Values Added
Description		Heap-based buffer overflow in Windows Kernel allows an authorized attacker to elevate privileges locally.
Title		Windows Kernel Elevation of Privilege Vulnerability
First Time appeared		Microsoft Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2025
Weaknesses		CWE-122
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_11_26H1:::::::arm64:* cpe:2.3:o:microsoft:windows_11_26H1:::::::x64:* cpe:2.3:o:microsoft:windows_server_2025::::::::
Vendors & Products		Microsoft Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2025
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21245
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: 2026-02-10T17:51:42.716Z

Updated: 2026-02-10T20:38:52.876Z

Reserved: 2025-12-11T21:02:05.735Z

Link: CVE-2026-21245

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-02-10T18:16:25.843

Modified: 2026-02-10T18:16:25.843

Link: CVE-2026-21245

Redhat

No data.

OpenCVE Enrichment

No data.

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