Windows Deployment Services (WDS) Remote Code Execution

Use after free in Windows Deployment Services allows an unauthorized attacker to execute code over a network.

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8.1CVSS out of 10Critical severity

Scope

What the vendor says is affected

Windows Server 2019
Windows Server 2019 (Server Core installation)
Windows Server 2022
Windows Server 2022 (Server Core installation)
Windows Server 2025 (Server Core installation)
Windows Server 2025
Windows Server 2016
Windows Server 2016 (Server Core installation)
Windows Server 2012
Windows Server 2012 (Server Core installation)
Windows Server 2012 R2
Windows Server 2012 R2 (Server Core installation)

Versions the vendor lists as fixed

10.0.17763.8880
10.0.20348.5256
10.0.26100.32995
10.0.14393.9234
6.2.9200.26132
6.3.9600.23228

Next step

What the vendor recommends

Install KB5094123. Install KB5094128. Install KB5094125. Install KB5094122. Install KB5094042. Install KB5094041.

Review the complete instructions on the vendor's site

Timeline

When this advisory changed

Jun 9, 2026 at 7:00 AM UTC
Published by Microsoft Security Response Center
The publication date reported by the vendor.
Sep 28, 2026 at 11:20 AM UTC
Added to SecurityAlert
We collected the advisory from the official source.

Vulnerabilities

CVEs named in this advisory

CVE-2026-42987View CVSS, KEV, EPSS, and threat context

Source

Start with the vendor's bulletin

SecurityAlert organizes the fields the vendor published. The original bulletin remains the source of record for affected versions, fixes, and later changes.

Vendor: Microsoft Security Response Center
Advisory ID: CVE-2026-42987
Last source check: Sep 28, 2026 at 11:20 AM UTC

Open the official bulletin How SecurityAlert builds this record

Your environment

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Read the vendor's prerequisites and exceptions.
Test the update or mitigation through your normal change process.

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What the vendor says is affected

Versions the vendor lists as fixed

What the vendor recommends

When this advisory changed

CVEs named in this advisory

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