Name: CVE-2026-21251: Use After Free
Creator: Rapid7
Published: 2026-02-10T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-21251, CVSS 7.8, EPSS 0.00445

Use after free in Windows Cluster Client Failover allows an authorized attacker to elevate privileges locally.

CVSS Details

CVSS 3.1 Base Score: 7.8
CVSS 3.1 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)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Microsoft Windows	—	2026-02 Cumulative Update for Microsoft Windows Server 2022, version 21H2 (KB5075906)2026-02 Cumulative Update for Microsoft Windows Server 2022, version 22H2 (KB5075906)2026-02 Cumulative Update for Microsoft Windows Server 2022, version 23H2 (KB5075897)2026-02 Cumulative Update for Microsoft Windows Server 2025, version 24H2 (KB5075899)2026-02 Cumulative Update for Microsoft Windows Server 2019, version 1809 (KB5075904)2026-02 Cumulative Update for Microsoft Windows Server 2016, version 1607 (KB5075999)	Feb 10, 2026	Feb 10, 2026

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CVSS Details

Covered by Rapid7

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