CVE-2026-33826: Microsoft Windows Server 2012

High severity, CVSS 8.0. EPSS: 0.5% chance of exploitation in the next 30 days.

Improper input validation in Windows Active Directory allows an authorized attacker to execute code over an adjacent network.

Affected products

• Microsoft Windows Server 2012: version r2 only
• Microsoft Windows Server 2016: before 10.0.14393.9060 (fixed in 10.0.14393.9060)
• Microsoft Windows Server 2019: before 10.0.17763.8644 (fixed in 10.0.17763.8644)
• Microsoft Windows Server 2022: before 10.0.20348.5020 (fixed in 10.0.20348.5020)
• Microsoft Windows Server 2022 23h2: before 10.0.25398.2274 (fixed in 10.0.25398.2274)
• Microsoft Windows Server 2025: before 10.0.26100.32690 (fixed in 10.0.26100.32690)

Published 2026-04-14. Last modified 2026-07-24.