CVEs / CVE-2025-59287
CVE-2025-59287: Microsoft Windows Server Update Service (WSUS) Deserialization of Untrusted Data Vulnerability
- Known exploited in the CISA KEV catalog since 24 Oct 2025
- critical 9.8 CVSS 3.1 (from the CNA)
- EPSS 99.9% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Microsoft Windows Server Update Service (WSUS) contains a deserialization of untrusted data vulnerability that allows for remote code execution.
Description
Deserialization of untrusted data in Windows Server Update Service allows an unauthorized attacker to execute code over a network.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Windows Server 2012 | from 6.2.9200.0, before 6.2.9200.25728 | 6.2.9200.25728 |
| Microsoft Windows Server 2012 (Server Core installation) | from 6.2.9200.0, before 6.2.9200.25728 | 6.2.9200.25728 |
| Microsoft Windows Server 2012 R2 | from 6.3.9600.0, before 6.3.9600.22826 | 6.3.9600.22826 |
| Microsoft Windows Server 2012 R2 (Server Core installation) | from 6.3.9600.0, before 6.3.9600.22826 | 6.3.9600.22826 |
| Microsoft Windows Server 2016 | from 10.0.14393.0, before 10.0.14393.8524 | 10.0.14393.8524 |
| Microsoft Windows Server 2016 (Server Core installation) | from 10.0.14393.0, before 10.0.14393.8524 | 10.0.14393.8524 |
| Microsoft Windows Server 2019 | from 10.0.17763.0, before 10.0.17763.7922 | 10.0.17763.7922 |
| Microsoft Windows Server 2019 (Server Core installation) | from 10.0.17763.0, before 10.0.17763.7922 | 10.0.17763.7922 |
| Microsoft Windows Server 2022 | from 10.0.20348.0, before 10.0.20348.4297 | 10.0.20348.4297 |
| Microsoft Windows Server 2022, 23H2 Edition (Server Core installation) | from 10.0.25398.0, before 10.0.25398.1916 | 10.0.25398.1916 |
| Microsoft Windows Server 2025 | from 10.0.26100.0, before 10.0.26100.6905 | 10.0.26100.6905 |
| Microsoft Windows Server 2025 (Server Core installation) | from 10.0.26100.0, before 10.0.26100.6905 | 10.0.26100.6905 |
Exploitation
| In CISA KEV since | 24 Oct 2025 |
|---|---|
| Due date for US federal agencies | 14 Nov 2025 |
| Used in ransomware campaigns | Unknown |
| 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. |
Severity
| CVSS 3.1 | 9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HScored by the CNA ([email protected]) |
|---|---|
| Weakness | CWE-502 |
References
- CVE-2025-59287 on NVD
- CVE-2025-59287 in the CISA KEV catalog
- https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2025-59287 (cited by CISA)
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-59287 Vendor Advisory
- https://hawktrace.com/blog/CVE-2025-59287 Exploit, Third Party Advisory
- https://www.bleepingcomputer.com/news/security/cisa-orders-feds-to-patch-windows-server-wsus-flaw-exploited-in-attacks/ Press/Media Coverage
- https://www.vicarius.io/vsociety/posts/cve-2025-59287-detection-script-rce-vulnerability-in-windows-server-update-service Third Party Advisory
- https://www.vicarius.io/vsociety/posts/cve-2025-59287-mitigation-script-rce-vulnerability-in-windows-server-update-service Mitigation, Third Party Advisory
- https://gist.github.com/hawktrace/880b54fb9c07ddb028baaae401bd3951 Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-59287 Third Party Advisory, US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.