CVE-2025-59287: Microsoft Windows Server Update Service (WSUS) Deserialization of Untrusted Data Vulnerability
Actively exploited. At least one CVE in this advisory is listed in the CISA Known Exploited Vulnerabilities catalog — exploitation has been observed in the wild. Treat remediation as urgent.
Microsoft Windows Server Update Service (WSUS) contains a deserialization of untrusted data vulnerability that allows for remote code execution.
CSIRTS triage
- What
- A deserialization of untrusted data vulnerability allows for remote code execution.
- Who is affected
- Deployments of Microsoft Windows Server Update Service.
- Urgency
- Immediate remediation is necessary as the vulnerability is actively exploited and rated critical.
- Action
- Install the latest updates from Microsoft.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2025-59287
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Exploitation confirmedCVE-2025-59287Already exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 100% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2025-59287 | coverage & exploitation status | NVD · CVE.org |
Recent advisories for Microsoft Windows Server
A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.
- high[UPDATE] [high] Microsoft Windows and Windows Server: Multiple vulnerabilitiescert-bund · 2026-07-06
- criticalexploitedCVE-2022-22047: Microsoft Windows Client Server Runtime Subsystem (CSRSS) Privilege Escalation Vulnerabilitycisa-kev · 2022-07-12
- criticalexploitedCVE-2019-1253: Microsoft Windows AppX Deployment Server Privilege Escalation Vulnerabilitycisa-kev · 2022-03-15
- criticalexploitedCVE-2020-1350: Microsoft Windows DNS Server Remote Code Execution Vulnerabilitycisa-kev · 2021-11-03
- criticalexploitedCVE-2017-0143: Microsoft Windows Server Message Block (SMBv1) Remote Code Execution Vulnerabilitycisa-kev · 2021-11-03
- criticalexploitedCVE-2017-7269: Microsoft Windows Server Buffer Overflow Vulnerabilitycisa-kev · 2021-11-03
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