Auth bypass in Microsoft Windows 10 Version 1607
CVE-2026-54121
Improper authorization in Active Directory Certificate Services (AD CS) allows an authorized attacker to elevate privileges over a network.
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Microsoft Windows 10 Version 1607 — versions 10.0.14393.0
- Microsoft Windows 10 Version 1809 — versions 10.0.17763.0
- Microsoft Windows Server 2012 — versions 6.2.9200.0
- Microsoft Windows Server 2012 R2 — versions 6.3.9600.0
- Microsoft Windows Server 2012 R2 (Server Core Installation) — versions 6.3.9600.0
- Microsoft Windows Server 2012 (Server Core Installation) — versions 6.2.9200.0
- Microsoft Windows Server 2016 — versions 10.0.14393.0
- Microsoft Windows Server 2016 (Server Core Installation) — versions 10.0.14393.0
- Microsoft Windows Server 2019 — versions 10.0.17763.0
- Microsoft Windows Server 2019 (Server Core Installation) — versions 10.0.17763.0
Weakness classification (CWE)
References
- secure@microsoft.com (vendor-advisory, patch)
Frequently asked questions
- What is CVE-2026-54121?
- CVE-2026-54121 is a high-severity vulnerability in Microsoft Windows 10 Version 1607, classified under Improper Authorization. CVSS score: 8.8/10. Published 2026-07-14.
- How severe is CVE-2026-54121?
- High severity. CVSS v3 base score is 8.8 out of 10.