CVE-2026-21251

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

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21251	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_server_2016::::::::
	cpe:2.3:o:microsoft:windows_server_2019::::::::
	cpe:2.3:o:microsoft:windows_server_2022::::::::
	cpe:2.3:o:microsoft:windows_server_2022_23h2::::::::
	cpe:2.3:o:microsoft:windows_server_2025::::::::

History

No history.

Information

Published : 2026-02-10 18:16

Updated : 2026-02-11 19:42

NVD link : CVE-2026-21251

Mitre link : CVE-2026-21251

CVE.ORG link : CVE-2026-21251

JSON object : View

Products Affected

microsoft

windows_server_2022
windows_server_2019
windows_server_2016
windows_server_2025
windows_server_2022_23h2

CWE

CWE-416

Use After Free

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