---
id: "CVE-2025-59287"
kind: "vulnerability"
aliases: ["CVE-2025-59287"]
title: "Deserialization of untrusted data in Windows Server Update Service allows an unauthorized attacker to execute code\u2026"
severity: "critical"
cvss: 9.8
epss: null
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Microsoft Windows", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "microsoft windows server 2012", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "microsoft windows server 2012", "fixed": [], "affected": "= r2", "ecosystem": "vendor"}, {"name": "microsoft windows server 2016", "fixed": ["10.0.14393.8524"], "affected": "< 10.0.14393.8524", "ecosystem": "vendor"}, {"name": "microsoft windows server 2019", "fixed": ["10.0.17763.7922"], "affected": "< 10.0.17763.7922", "ecosystem": "vendor"}, {"name": "microsoft windows server 2022", "fixed": ["10.0.20348.4297"], "affected": "< 10.0.20348.4297", "ecosystem": "vendor"}, {"name": "microsoft windows server 2022 23h2", "fixed": ["10.0.25398.1916"], "affected": "< 10.0.25398.1916", "ecosystem": "vendor"}, {"name": "microsoft windows server 2025", "fixed": ["10.0.26100.6905"], "affected": "< 10.0.26100.6905", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "infrastructure", "windows", "windows-server", "wsus"]
not_affected_if: ["no-wsus-role"]
published_at: "2025-10-14T17:16:11+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T23:44:51+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2025-59287", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-59287", "first_seen_at": "2026-10-23T23:44:51+00:00"}]
---

# Deserialization of untrusted data in Windows Server Update Service allows an unauthorized attacker to execute code…

Microsoft Windows Server Update Services (WSUS) has a deserialization flaw that lets a remote party run code on the server. CISA lists it as actively exploited in the wild.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Microsoft Windows affected ? fixed ?
- vendor:microsoft windows server 2012 affected ? fixed ?
- vendor:microsoft windows server 2012 affected = r2 fixed ?
- vendor:microsoft windows server 2016 affected < 10.0.14393.8524 fixed 10.0.14393.8524
- vendor:microsoft windows server 2019 affected < 10.0.17763.7922 fixed 10.0.17763.7922
- vendor:microsoft windows server 2022 affected < 10.0.20348.4297 fixed 10.0.20348.4297
- vendor:microsoft windows server 2022 23h2 affected < 10.0.25398.1916 fixed 10.0.25398.1916
- vendor:microsoft windows server 2025 affected < 10.0.26100.6905 fixed 10.0.26100.6905

## Fix

Apply the Microsoft mitigations or patch for CVE-2025-59287 per vendor instructions; if no mitigation is available, stop using WSUS.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2025-59287
- 2026-10-23T23:44:51+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2025-59287

## From the sources

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

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.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_