CVE-2026-20866

HighCVSS 7.8/10Last modified Jul 30, 2026

Description

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Management Services allows an authorized attacker to elevate privileges locally.

Metrics

CVSS 3.1 7.8/10CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

Weakness enumeration

CWE-362

Affected software

Vendor	Product	Versions
Microsoft	Windows 10 Version 1809	>= 10.0.17763.0, < 10.0.17763.8276
Microsoft	Windows 10 Version 21H2	>= 10.0.19044.0, < 10.0.19044.6809
Microsoft	Windows 10 Version 22H2	>= 10.0.19045.0, < 10.0.19045.6809
Microsoft	Windows 11 version 23H2	>= 10.0.22631.0, < 10.0.22631.6491
Microsoft	Windows 11 Version 23H2	>= 10.0.22631.0, < 10.0.22631.6491
Microsoft	Windows 11 Version 24H2	>= 10.0.26100.0, < 10.0.26100.7623
Microsoft	Windows 11 Version 25H2	>= 10.0.26200.0, < 10.0.26200.7623
Microsoft	Windows Server 2019	>= 10.0.17763.0, < 10.0.17763.8276
Microsoft	Windows Server 2019 (Server Core installation)	>= 10.0.17763.0, < 10.0.17763.8276
Microsoft	Windows Server 2022	>= 10.0.20348.0, < 10.0.20348.4648
Microsoft	Windows Server 2022, 23H2 Edition (Server Core installation)	>= 10.0.25398.0, < 10.0.25398.2092
Microsoft	Windows Server 2025	>= 10.0.26100.0, < 10.0.26100.32230
Microsoft	Windows Server 2025 (Server Core installation)	>= 10.0.26100.0, < 10.0.26100.32230

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20866Vendor Advisory

Timeline

Published: Jan 13, 2026
Last modified: Jul 30, 2026
NVD status: Analyzed

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