CVE-2024-21338: Microsoft Windows Kernel Exposed IOCTL with Insufficient Access Control Vulnerability

High severity, CVSS 7.8. Actively exploited: in CISA KEV since 2024-03-04. EPSS: 59.8% chance of exploitation in the next 30 days.

Windows Kernel Elevation of Privilege Vulnerability

Affected products

• Microsoft Windows 10 1809: before 10.0.17763.5458 (fixed in 10.0.17763.5458)
• Microsoft Windows 10 21h2: before 10.0.19044.4046 (fixed in 10.0.19044.4046)
• Microsoft Windows 10 22h2: before 10.0.19045.4046 (fixed in 10.0.19045.4046)
• Microsoft Windows 11 21h2: before 10.0.22000.2777 (fixed in 10.0.22000.2777)
• Microsoft Windows 11 22h2: before 10.0.22621.3155 (fixed in 10.0.22621.3155)
• Microsoft Windows 11 23h2: before 10.0.22631.3155 (fixed in 10.0.22631.3155)
• Microsoft Windows Server 2019: before 10.0.17763.5458 (fixed in 10.0.17763.5458)
• Microsoft Windows Server 2022: before 10.0.20348.2322 (fixed in 10.0.20348.2322)
• Microsoft Windows Server 2022 23h2: up to and including 10.0.25398.709

Published 2024-02-13. Last modified 2026-08-10.