Applied Cybernetics Group
Threat intel → detection pipeline
Tuesday, July 14, 2026
Data as of 20:11 UTC

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

Added to KEV
2025-10-24
Federal due date
2025-11-14
Vendor
Microsoft
Product
Windows
EPSS
100.0th percentile (score 1.000, as of 2026-07-13)
NVD CVSS v3.1
9.8 (CRITICAL)
Ransomware use
Unknown
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2025-59287

CISA short description

Microsoft Windows Server Update Service (WSUS) contains a deserialization of untrusted data vulnerability that allows for remote code execution.

Required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

NVD description

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

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.