Description
Windows Update Service Elevation of Privilege Vulnerability
Affected products
microsoft: windows 10; microsoft: windows server 2016; microsoft: windows server 2019
References3
- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-… PatchVendor Advisory
- msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26866
- www.zerodayinitiative.com/advisories/ZDI-21-286/ Third Party AdvisoryVDB Entry
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H - EPSS — exploit probability
- 1% percentile: 67 · as of 11 November 2026
- CWE
- CWE-59
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