Risk Letters

Exploited vulnerability

CVE-2025-59287

TLP:CLEAR

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

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

Facts

  • Vendor: Microsoft
  • Product: Windows
  • CVSS: 9.8
  • EPSS (probability of exploitation within 30 days): 100 %
  • On CISA's Known Exploited Vulnerabilities list since: 24 October 2025
  • First known exploitation: 24 October 2025
  • CISA's deadline for US federal agencies: 14 November 2025
  • Weakness: CWE-502
  • First seen by Risk Letters: 24 October 2025

Members see which Nordic sectors the flaw hits, and what to do about it.

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Data: NVD (public domain), CISA KEV, FIRST EPSS, MITRE ATT&CK, AlienVault OTX. NVD