Vulnerability · NVD
CVE-2026-66799
CRITICAL 7.8
Vendor bulletin scale — NVD CVSS pending
Windows Key Guard Elevation of Privilege Vulnerability
OS versions that fix this CVE
This CVE is resolved by the following OS security releases. Update the OS to at least the listed version.
- Windows Server 2025 Fixed in 10.0.26100.33296
- Windows Server 2022 Fixed in 10.0.20348.5499
- Windows Server 2019 Fixed in 10.0.17763.9115
- Windows Server 2016 Fixed in 10.0.14393.9418
- Windows 11 26H1 · 2026-H1 Fixed in 10.0.28000.2704
- Windows 11 25H2 · 2025-H2 Fixed in 10.0.26200.9168
- Windows 11 24H2 · 2024-H2 Fixed in 10.0.26100.9168
- Windows 11 23H2 · 2023-H2 Fixed in 10.0.22631.7517
- Windows 10 22H2 · 2022-H2 Fixed in 10.0.19045.7663
- Windows 10 21H2 · 2021-H2 Fixed in 10.0.19044.7663
- Windows 10 1809 · 2018-09 Fixed in 10.0.17763.9115
- Windows 10 1607 · 2016-07 Fixed in 10.0.14393.9418