Input validation error in Microsoft Windows and Windows Server - CVE-2026-45642

Vulnerability identifier: #VU134264

CSH Severity: Low

CVSS v4: 5.1 [CVSS:4.0/AV:P/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-45642

CWE-ID: CWE-20

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to compromise the target system.

The vulnerability exists due to insufficient validation of user-supplied input in Microsoft Azure Attestation service and Device Health Attestation Service. An administrator with physical access can perform spoofing attack on the system.

Microsoft Windows
Windows Server

Install updates from vendor's website.

Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7417, 10 22H2 10.0.19045.7417, 10 1607 10.0.14393.9234, 10 1809 10.0.17763.8880, 11 23H2 10.0.22631.7219, 11 24H2 10.0.26100.8655, 11 25H2 10.0.26200.8655, 11 26H1 10.0.28000.2269
Windows Server - addressed in versions 2004 10.0.19045.7417, 2012 R2 6.3.9600.23228, 2012 6.2.9200.26132, 2016 10.0.14393.9234, 2019 10.0.17763.8880, 2022 10.0.20348.5256, 2025 10.0.26100.32995

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45642

• Spoofing attack in Microsoft Azure Attestation service and Device Health Attestation Service