Use of a broken or risky cryptographic algorithm in Microsoft Windows and Windows Server - CVE-2026-50303
Published: July 17, 2026
Vulnerability identifier: #VU137993
CSH Severity: Low
CVSS v4: 6.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-50303
CWE-ID: CWE-327
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to bypass the authentication feature.
The vulnerability exists due to use of a cryptographic primitive with a risky implementation in Windows Key Guard when processing authentication operations. A local user can exploit the flawed cryptographic implementation to bypass the authentication feature.
This vulnerability can enable impersonation.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-50303
Install security update from vendor's website.
Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7548, 10 22H2 10.0.19045.7548, 10 1809 10.0.17763.9020, 11 24H2 10.0.26100.8875, 11 25H2 10.0.26200.8875, 11 26H1 10.0.28000.2269, 11 26H1 10.0.28000.2525
Windows Server - addressed in versions 2012 R2 6.3.9600.23291, 2019 10.0.17763.9020, 2022 10.0.20348.5386, 2025 10.0.26100.33158
Windows Server - addressed in versions 2012 R2 6.3.9600.23291, 2019 10.0.17763.9020, 2022 10.0.20348.5386, 2025 10.0.26100.33158