#VU107263 Improper access control in Windows and Windows Server - CVE-2025-26678

Vulnerability identifier: #VU107263

Vulnerability risk: Low

CVSSv4.0: 6.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-26678

CWE-ID: CWE-284

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Windows
Operating systems & Components / Operating system
Windows Server
Operating systems & Components / Operating system

Vendor: Microsoft

Description

The vulnerability allows a local attacker to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to improper access restrictions in Windows Defender Application Control. A local attacker can bypass Windows Defender Application Control (WDAC) enforcement.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Windows: 10 21H2 10.0.19041.3920 - 10 21H2 10.0.19044.5608, 10 22H2 10.0.19041.3920 - 10 22H2 10.0.19045.5608, 10 1607 10.0.14393.10 - 10 1607 10.0.14393.7876, 10 1809 10.0.17763.1 - 10 1809 10.0.17763.7009, 11 22H2 10.0.22449.1000 - 11 22H2 10.0.22621.5039, 11 23H2 10.0.22631.1825 - 11 23H2 10.0.22631.5039, 11 24H2 10.0.26052.1000 - 11 24H2 10.0.26100.3476

Windows Server: 2012 R2 6.3.9600.21871 - 2012 R2 6.3.9600.22470, 2019 10.0.17763.1 - 2019 10.0.17763.7009, 2022 10.0.20348.202 - 2022 23H2 10.0.25398.1486, 2025 10.0.26100.1742 - 2025 10.0.26100.3476

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External links
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-26678

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.