CVE-2026-54121
HIGHCVSS 8.8/10EPSS 0.80%
Last modified
CVE-2026-54121 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. Improper authorization in Active Directory Certificate Services (AD CS) allows an authorized attacker to elevate privileges over a network.. EPSS estimates a 0.80% chance of exploitation in the next 30 days.
Description
Improper authorization in Active Directory Certificate Services (AD CS) allows an authorized attacker to elevate privileges over a network.
Metrics
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows 10 1607 | < 10.0.14393.9339 |
| Microsoft | Windows 10 1809 | < 10.0.17763.9020 |
| Microsoft | Windows Server 2012 | All versions |
| Microsoft | Windows Server 2012 | r2 |
| Microsoft | Windows Server 2016 | < 10.0.14393.9339 |
| Microsoft | Windows Server 2019 | < 10.0.17763.9020 |
| Microsoft | Windows Server 2022 | < 10.0.20348.5386 |
| Microsoft | Windows Server 2025 | < 10.0.26100.33158 |
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-54121Patch, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-54121?
Improper authorization in Active Directory Certificate Services (AD CS) allows an authorized attacker to elevate privileges over a network.
How severe is CVE-2026-54121?
CVE-2026-54121 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 0.80% probability of exploitation in the next 30 days.
How do I fix CVE-2026-54121?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
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Are you affected by CVE-2026-54121?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST