Privilege Escalation Vulnerability in Windows Management Services by Microsoft
CVE-2026-20866

7.8HIGH

Key Information:

Vendor

Microsoft
Status
Windows 10 Version 1809
Windows Server 2019
Windows Server 2019 (server Core Installation)
Windows Server 2022
Vendor
CVE Published:
13 January 2026

What is CVE-2026-20866?

A race condition in Windows Management Services can allow an authorized attacker to execute concurrent processes with improper synchronization, potentially enabling them to elevate their privileges locally. This vulnerability underscores the importance of implementing stringent access controls and updating systems to mitigate the risks associated with privilege escalation.

Affected Version(s)

Windows 10 Version 1809 32-bit Systems 10.0.17763.0 < 10.0.17763.8276

Windows 10 Version 21H2 32-bit Systems 10.0.19044.0 < 10.0.19044.6809

Windows 10 Version 22H2 x64-based Systems 10.0.19045.0 < 10.0.19045.6809

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE...
vendor-advisorypatch

CVSS V3.1

Score:
7.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
High
Privileges Required:
Low
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

JSON
.