CVE-2026-69588: Microsoft Windows 11 23h2

High severity, CVSS 7.5. EPSS: 1.2% chance of exploitation in the next 30 days.

Missing release of memory after effective lifetime in Windows TCP/IP allows an unauthorized attacker to deny service over a network.

Affected products

• Microsoft Windows 11 23h2: before 10.0.22631.7582 (fixed in 10.0.22631.7582)
• Microsoft Windows 11 24h2: before 10.0.26100.9445 (fixed in 10.0.26100.9445)
• Microsoft Windows 11 25h2: before 10.0.26200.9445 (fixed in 10.0.26200.9445)
• Microsoft Windows 11 26h1: before 10.0.28000.2954 (fixed in 10.0.28000.2954)
• Microsoft Windows Server 2022: before 10.0.20348.5622 (fixed in 10.0.20348.5622)
• Microsoft Windows Server 2025: before 10.0.26100.33438 (fixed in 10.0.26100.33438)

Published 2026-09-08. Last modified 2026-09-18.