---
id: CVE-2026-54121
title: Active Directory Certificate Services Elevation of Privilege Vulnerability
summary: >-
  Improper authorization in Active Directory Certificate Services (AD CS) allows
  an authorized attacker to elevate privileges over a network.
severity: high
cvss: 8.8
cvssVector: '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'
cvssSource: cna
cwe:
  - CWE-285
vendor: Microsoft
product: Windows 10 Version 1607
affected:
  - windows_10_version_1607 >= 10.0.14393.0 < 10.0.14393.9339
  - windows_10_version_1809 >= 10.0.17763.0 < 10.0.17763.9020
  - windows_server_2012 >= 6.2.9200.0 < 6.2.9200.26226
  - windows_server_2012_server_core_installation >= 6.2.9200.0 < 6.2.9200.26226
  - windows_server_2012_r2 >= 6.3.9600.0 < 6.3.9600.23291
  - >-
    windows_server_2012_r2_server_core_installation >= 6.3.9600.0 <
    6.3.9600.23291
  - windows_server_2016 >= 10.0.14393.0 < 10.0.14393.9339
  - >-
    windows_server_2016_server_core_installation >= 10.0.14393.0 <
    10.0.14393.9339
  - windows_server_2019 >= 10.0.17763.0 < 10.0.17763.9020
  - >-
    windows_server_2019_server_core_installation >= 10.0.17763.0 <
    10.0.17763.9020
  - windows_server_2022 >= 10.0.20348.0 < 10.0.20348.5386
  - windows_server_2025 >= 10.0.26100.0 < 10.0.26100.33158
  - >-
    windows_server_2025_server_core_installation >= 10.0.26100.0 <
    10.0.26100.33158
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-07-10T00:00:00+00:00'
exploitAvailable: true
published: '2026-07-14'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T18:23:34.824Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-54121'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-54121'
    label: Active Directory Certificate Services Elevation of Privilege Vulnerability
tags:
  - cve.org
  - exploit-available
epss: 0.00778
epssPercentile: 0.53921
exploits:
  github: 13
  githubRepos:
    - 'https://github.com/aniqfakhrul/CVE-2026-54121'
    - 'https://github.com/ZeroDayEvil/CVE-2026-54121-Certighost'
    - 'https://github.com/tc4dy/CVE-2026-54121-PoC-Exploit'
  checkedAt: '2026-09-25T19:16:13.571Z'
ingestedAt: '2026-09-08T17:06:31.912Z'
---

## Overview

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

## Affected

- `windows_10_version_1607 >= 10.0.14393.0 < 10.0.14393.9339`
- `windows_10_version_1809 >= 10.0.17763.0 < 10.0.17763.9020`
- `windows_server_2012 >= 6.2.9200.0 < 6.2.9200.26226`
- `windows_server_2012_server_core_installation >= 6.2.9200.0 < 6.2.9200.26226`
- `windows_server_2012_r2 >= 6.3.9600.0 < 6.3.9600.23291`
- `windows_server_2012_r2_server_core_installation >= 6.3.9600.0 < 6.3.9600.23291`
- `windows_server_2016 >= 10.0.14393.0 < 10.0.14393.9339`
- `windows_server_2016_server_core_installation >= 10.0.14393.0 < 10.0.14393.9339`
- `windows_server_2019 >= 10.0.17763.0 < 10.0.17763.9020`
- `windows_server_2019_server_core_installation >= 10.0.17763.0 < 10.0.17763.9020`
- `windows_server_2022 >= 10.0.20348.0 < 10.0.20348.5386`
- `windows_server_2025 >= 10.0.26100.0 < 10.0.26100.33158`
- `windows_server_2025_server_core_installation >= 10.0.26100.0 < 10.0.26100.33158`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.