ClosedPatched

Microsoft Windows: Windows Server Update Service (WSUS) Deserialization of Untrusted Data Vulnerability

Microsoft Windows

Microsoft Windows Server Update Service (WSUS) contains a deserialization of untrusted data vulnerability that allows for remote code execution. Added to CISA KEV on 2025-10-24.

Why this severity: CVSS 9.8 (CNA, v3.1); actively exploited (CISA KEV)

Started: Oct 24, 2025
Closed: Oct 24, 2025
CVE: CVE-2025-59287

Follow this incident

Updated Oct 24, 2025

Affected

See vendor advisory / CISA notes (versions not always listed in KEV feed)

Fixed in

See vendor advisory linked in sources

Timeline1

Oct 24, 2025
CISA added CVE-2025-59287 to the KEV catalog (due 2025-11-14).

Advisories3

Notes & caveats

Derived from CISA KEV JSON feed catalogVersion 2026.10.21. CVSS from the CVE record (cvelistV5). Exact affected/fixed version strings are not always in the KEV record; verify against the vendor advisory URL. startedAt uses dateAdded (exploitation may have begun earlier; many entries are older CVEs newly confirmed as exploited in 2025).

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