CVE-2025-59287
Microsoft Windows Server Update Service (WSUS) Deserialization of Untrusted Data Vulnerability
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run Windows, fix it now.
CISA 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.
US federal civilian agencies must remediate by Nov 14, 2025.
Patch status
No official fix confirmed yet
Until a fix ships, follow the vendor's mitigations and CISA's required action, limit exposure of affected systems, and watch this record for a patch.
Description
Deserialization of untrusted data in Windows Server Update Service allows an unauthorized attacker to execute code over a network.
Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.
Affected products
| Product | Vendor | Source |
|---|---|---|
| Windows | Microsoft | KEV |
Sources: KEV = CISA Known Exploited Vulnerabilities catalog. Version details have not been published yet.
Intelligence timeline
Developments from the last 30 days, newest first.
- CVSS scoredUpdateKEV
CVE-2025-59287 scored CVSS 9.8: Microsoft Windows, Microsoft Windows Server Update Service (WSUS) Deserialization of Untrusted Data Vulnerability
CISA lists this as exploited in the wild. Unpatched Windows systems are exposed to active attacks now.
Basis: NIST National Vulnerability Database
1 earlier event is available with a subscription. See plans.
Coverage
We have not published a story about this vulnerability yet.