Microsoft Security Response CenterCVE-2026-50508

Windows NTLM Spoofing Vulnerability

Exposure of sensitive information to an unauthorized actor in Windows NTLM allows an unauthorized attacker to perform spoofing over a network.

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6.5CVSS out of 10High severity

Scope

What the vendor says is affected

Windows Server 2022
Windows Server 2022 (Server Core installation)
Windows Server, version 2004 (Server Core installation)
Windows 11 Version 22H2 for ARM64-based Systems
Windows 11 Version 22H2 for x64-based Systems
Windows 10 Version 1607 for 32-bit Systems
Windows 10 Version 1607 for x64-based Systems
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

10.0.20348.5256
10.0.19045.7417
10.0.22631.7219
10.0.14393.9234
6.2.9200.26132
6.3.9600.23228

Next step

What the vendor recommends

Install KB5094128. Install KB5094127. Install KB5093998. 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-2026-50508View CVSS, KEV, EPSS, and threat context

Source

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Vendor: Microsoft Security Response Center
Advisory ID: CVE-2026-50508
Last source check: Sep 28, 2026 at 11:20 AM UTC

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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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