Windows Kernel Memory Elevation of Privilege Vulnerability
This high-severity Microsoft Server advisory covers CVE-2026-20809 affecting Windows Server 2012 R2 (Server Core installation), Windows Server 2016 (Server Core installation), Windows Server 2019 (Server Core installation).
Android app · Google Play
Monitor future Microsoft Server CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
Time-of-check time-of-use (toctou) race condition in Windows Kernel Memory allows an authorized attacker to elevate privileges locally.
Affected products named by the advisory: Windows Server 2012 R2; Windows Server 2012 R2 (Server Core installation); Windows Server 2016; Windows Server 2016 (Server Core installation); and 6 more.
Affected products named by the advisory: Windows Server 2019 (Server Core installation); Windows Server 2022, 23H2 Edition (Server Core installation); Windows Server 2025 (Server Core installation).
- Windows 10 Version 1607 10.0.14393.0 before 10.0.14393.8783
- Windows 10 Version 1809 10.0.17763.0 before 10.0.17763.8276
- Windows 10 Version 21H2 10.0.19044.0 before 10.0.19044.6809
- Windows 10 Version 22H2 10.0.19045.0 before 10.0.19045.6809
- Windows 11 version 23H2 10.0.22631.0 before 10.0.22631.6491
- Windows 11 Version 23H2 10.0.22631.0 before 10.0.22631.6491
- Windows 11 Version 24H2 10.0.26100.0 before 10.0.26100.7623
- Windows 11 Version 25H2 10.0.26200.0 before 10.0.26200.7623
- Windows Server 2012 R2 6.3.9600.0 before 6.3.9600.22968
- Windows Server 2012 R2 (Server Core installation) 6.3.9600.0 before 6.3.9600.22968
- Windows Server 2016 10.0.14393.0 before 10.0.14393.8783
- Windows Server 2016 (Server Core installation) 10.0.14393.0 before 10.0.14393.8783
Official advisory · high-confidence parse· fetched 2 hours ago·verify at source
- 10.0.14393.8783
- 10.0.17763.8276
- 10.0.19044.6809
- 10.0.19045.6809
- 10.0.22631.6491
- 10.0.26100.7623
- 10.0.26200.7623
- 6.3.9600.22968
- 10.0.20348.4648
- 10.0.25398.2092
- 10.0.26100.32230
Official advisory · high-confidence parse· fetched 2 hours ago·verify at source
Mitigation
Upgrade to a fixed release: 10.0.14393.8783, 10.0.17763.8276, 10.0.19044.6809, 10.0.19045.6809, 10.0.22631.6491, 10.0.26100.7623. That is the remediation for this advisory.
The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.
Official advisory · high-confidence parse· fetched 2 hours ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.