Missing Required Cryptographic Step in Windows and Windows Server - CVE-2026-58638
Published: July 17, 2026
Vulnerability identifier: #VU138166
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-58638
CWE-ID: CWE-325
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Microsoft
Affected software:
Windows
Windows Server
Windows
Windows Server
Detailed vulnerability description
The vulnerability allows a local user to bypass a security feature.
The vulnerability exists due to missing cryptographic step in Windows Boot Loader when processing the boot sequence. A local user can leverage the flaw locally to bypass a security feature.
How to mitigate CVE-2026-58638
Install security update from vendor's website.