CVE-2025-59287: Microsoft Windows Server Update Service (WSUS) Deserialization of Untrusted Data Vulnerability

Critical severity, CVSS 9.8. Actively exploited: in CISA KEV since 2025-10-24. EPSS: 100% chance of exploitation in the next 30 days.

Deserialization of untrusted data in Windows Server Update Service allows an unauthorized attacker to execute code over a network.

Affected products

• Microsoft Windows Server 2012: affected versions not specified; version r2 only
• Microsoft Windows Server 2016: before 10.0.14393.8524 (fixed in 10.0.14393.8524)
• Microsoft Windows Server 2019: before 10.0.17763.7922 (fixed in 10.0.17763.7922)
• Microsoft Windows Server 2022: before 10.0.20348.4297 (fixed in 10.0.20348.4297)
• Microsoft Windows Server 2022 23h2: before 10.0.25398.1916 (fixed in 10.0.25398.1916)
• Microsoft Windows Server 2025: before 10.0.26100.6905 (fixed in 10.0.26100.6905)

Published 2025-10-14. Last modified 2026-06-17.