CVE-2025-62456: Microsoft Windows 11 23h2

High severity, CVSS 8.8. EPSS: 1.1% chance of exploitation in the next 30 days.

Heap-based buffer overflow in Windows Resilient File System (ReFS) allows an authorized attacker to execute code over a network.

Affected products

• Microsoft Windows 11 23h2: before 10.0.22631.6345 (fixed in 10.0.22631.6345)
• Microsoft Windows 11 24h2: before 10.0.26100.7392 (fixed in 10.0.26100.7392)
• Microsoft Windows 11 25h2: before 10.0.26200.7392 (fixed in 10.0.26200.7392)
• Microsoft Windows Server 2022: before 10.0.20348.4467 (fixed in 10.0.20348.4467)
• Microsoft Windows Server 2022 23h2: before 10.0.25398.2025 (fixed in 10.0.25398.2025)
• Microsoft Windows Server 2025: before 10.0.26100.7392 (fixed in 10.0.26100.7392)

Published 2025-12-09. Last modified 2026-10-07.