Windows Network Controller (NC) Host Agent Denial of Service Vulnerability

Use after free in Windows Network Controller (NC) Host Agent allows an authorized attacker to deny service locally.

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5.5CVSS out of 10High 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

Versions the vendor lists as fixed

10.0.17763.8880
10.0.20348.5256
10.0.26100.32995

Next step

What the vendor recommends

Install KB5094123. Install KB5094128. Install KB5094125.

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-2026-44805View CVSS, KEV, EPSS, and threat context

Source

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Vendor: Microsoft Security Response Center
Advisory ID: CVE-2026-44805
Last source check: Sep 28, 2026 at 11:20 AM UTC

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Your environment

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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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