CVE-2026-88091: Microsoft Windows 10 1607

High severity, CVSS 7.8. EPSS: 2.9% chance of exploitation in the next 30 days.

Deserialization of untrusted data in Windows Management Instrumentation allows an authorized attacker to elevate privileges locally.

Affected products

• Microsoft Windows 10 1607: before 10.0.14393.9612 (fixed in 10.0.14393.9612)
• Microsoft Windows 10 1809: before 10.0.17763.9376 (fixed in 10.0.17763.9376)
• Microsoft Windows 10 21h2: before 10.0.19044.7807 (fixed in 10.0.19044.7807)
• Microsoft Windows 10 22h2: before 10.0.19045.7807 (fixed in 10.0.19045.7807)
• Microsoft Windows 11 23h2: before 10.0.22631.7652 (fixed in 10.0.22631.7652)
• Microsoft Windows 11 24h2: before 10.0.26100.9711 (fixed in 10.0.26100.9711)
• Microsoft Windows 11 25h2: before 10.0.26200.9711 (fixed in 10.0.26200.9711)
• Microsoft Windows 11 26h1: before 10.0.28000.3231 (fixed in 10.0.28000.3231)
• Microsoft Windows 11 26h2: before 10.0.26300.9711 (fixed in 10.0.26300.9711)
• Microsoft Windows Server 2012: affected versions not specified; version r2 only
• Microsoft Windows Server 2016: before 10.0.14393.9612 (fixed in 10.0.14393.9612)
• Microsoft Windows Server 2019: before 10.0.17763.9376 (fixed in 10.0.17763.9376)
• Microsoft Windows Server 2022: before 10.0.20348.5761 (fixed in 10.0.20348.5761)
• Microsoft Windows Server 2025: before 10.0.26100.33650 (fixed in 10.0.26100.33650)

Published 2026-10-13. Last modified 2026-10-16.