CyberICT

CVE-2026-21251

Microsoft · Published February 10, 2026

CVSS v3.1

HIGH
Patch availableGet patch

Description

Cluster Client Failover (CCF) Elevation of Privilege Vulnerability. Use after free in Windows Cluster Client Failover allows an authorized attacker to elevate privileges locally.

Affected Products

  • Windows Server 2019
  • Windows Server 2019 (Server Core installation)
  • Windows Server 2022
  • Windows Server 2022 (Server Core installation)

CVSS 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