CVE-2026-54121: Active Directory Certificate Services Elevation of Privilege Vulnerability

Overview

Severity
High (CVSS 8.8)
CVSS Vector
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
Category
Elevation of Privilege
Exploit Status
Not Exploited
Exploitation Likelihood
Less Likely
Patch Tuesday
2026-Jul
Released
2026-07-14

Description

Improper authorization in Active Directory Certificate Services (AD CS) allows an authorized attacker to elevate privileges over a network.

FAQ

What privileges could be gained by an attacker who successfully exploited the vulnerability? An attacker who successfully exploited this vulnerability could gain administrator privileges. How could an attacker exploit this vulnerability? An authenticated attacker could manipulate attributes associated with a machine account and obtain a certificate from Active Directory Certificate Services that allows authentication as that machine via PKINIT. If a Domain Controller account can be targeted, the attacker could authenticate as the Domain Controller and gain the ability to perform privileged Active Directory operations.

Affected Products (15)

Windows

  • Windows 10 Version 1809 for 32-bit Systems
  • Windows 10 Version 1809 for x64-based Systems
  • Windows Server 2019
  • Windows Server 2019 (Server Core installation)
  • Windows Server 2022
  • Windows Server 2025 (Server Core installation)
  • Windows Server 2025
  • Windows 10 Version 1607 for 32-bit Systems
  • Windows 10 Version 1607 for x64-based Systems
  • Windows Server 2016
  • Windows Server 2016 (Server Core installation)

ESU

  • Windows Server 2012
  • Windows Server 2012 (Server Core installation)
  • Windows Server 2012 R2
  • Windows Server 2012 R2 (Server Core installation)

Security Updates (6)

Acknowledgments

<a href="https://x.com/aniqfakhrul">Aniq Fakhrul</a> <a href="https://x.com/h0j3n">Muhammad Ali</a>, <a href="https://x.com/aniqfakhrul">Aniq Fakhrul</a>, <a href="https://x.com/aniqfakhrul">Aniq Fakhrul</a> <a href="https://x.com/h0j3n">Muhammad Ali</a>

Revision History

  • 2026-07-14: Information published.