Windows DWM Core Library Elevation of Privilege Vulnerability

Use after free in Windows DWM Core Library allows an authorized attacker to elevate privileges over a network.

Read the vendor bulletin Get alerts for Windows Server 2025 (Server Core installation)

7.1CVSS out of 10High severity

Scope

What the vendor says is affected

Windows Server 2025 (Server Core installation)
Windows 11 Version 23H2 for ARM64-based Systems
Windows 11 Version 23H2 for x64-based Systems
Windows Server 2025

Versions the vendor lists as fixed

10.0.26100.33438
10.0.22631.7582

Next step

What the vendor recommends

Install KB5122871. Install KB5122880.

Review the complete instructions on the vendor's site

Timeline

When this advisory changed

Sep 8, 2026 at 7:00 AM UTC
Published by Microsoft Security Response Center
The publication date reported by the vendor.
Sep 8, 2026 at 7:15 PM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Sep 13, 2026 at 2:40 AM UTC
Confirmed at the source
Our collector saw this advisory during a later source check.

Vulnerabilities

CVEs named in this advisory

CVE-2026-69775View CVSS, KEV, EPSS, and threat context

Source

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Vendor: Microsoft Security Response Center
Advisory ID: CVE-2026-69775
Last source check: Sep 13, 2026 at 2:40 AM UTC

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Your environment

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Test the update or mitigation through your normal change process.

Watch Windows Server 2025 (Server Core installation)

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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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