CVE-2026-54121 json
Active Directory Certificate Services Elevation of Privilege Vulnerability
published 2026-07-14 3 mo ago modified 2026-11-01 7 d ago also EUVD-2026-44139
- cvss
- 8.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.8%
- EPSS 1.8% chance of exploitation in 30 days, percentile 79%
- public exploits
- 0
- none known
Summary
Improper authorization in Active Directory Certificate Services (AD CS) allows an authorized attacker to elevate privileges over a network.
Patch / fix
- Microsoft Windows 10 Version 1607 10.0.14393.9339
- Microsoft Windows 10 Version 1809 10.0.17763.9020
- Microsoft Windows Server 2012 6.2.9200.26226
- Microsoft Windows Server 2012 (Server Core installation) 6.2.9200.26226
- Microsoft Windows Server 2012 R2 6.3.9600.23291
- Microsoft Windows Server 2012 R2 (Server Core installation) 6.3.9600.23291
- Microsoft Windows Server 2016 10.0.14393.9339
- Microsoft Windows Server 2016 (Server Core installation) 10.0.14393.9339
- Microsoft Windows Server 2019 10.0.17763.9020
- Microsoft Windows Server 2019 (Server Core installation) 10.0.17763.9020
- Microsoft Windows Server 2022 10.0.20348.5386
- Microsoft Windows Server 2025 10.0.26100.33158
- Microsoft Windows Server 2025 (Server Core installation) 10.0.26100.33158
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 4 mo ago
Exploit prediction
1.84% chance of exploitation in the next 30 days, higher than 79% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C |
| CNA | 3.1 | 8.8 | 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
- Microsoft Windows 10 Version 1809
- Microsoft Windows Server 2012
- Microsoft Windows Server 2012 (Server Core installation)
- Microsoft Windows Server 2012 R2
- Microsoft Windows Server 2012 R2 (Server Core installation)
- Microsoft Windows Server 2016
- Microsoft Windows Server 2016 (Server Core installation)
- Microsoft Windows Server 2019
- Microsoft Windows Server 2019 (Server Core installation)
- Microsoft Windows Server 2022
- Microsoft Windows Server 2025
- Microsoft Windows Server 2025 (Server Core installation)
Classification
- Weakness
-
- CWE-285 Improper Authorization
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2026-54121
vendor-advisory, patch
Sources
- CVE List CVE-2026-54121
- NVD CVE-2026-54121
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.