CVE-2025-27740: Active Directory Certificate Services Elevation of Privilege Vulnerability

CVE-2025-27740 is an elevation of privilege vulnerability in Active Directory Certificate Services, rated Important by Microsoft, with a CVSS 3.1 base score of 8.8 (High). An attacker can exploit it remotely over the network, with low privileges and without user interaction. Microsoft has not reported exploitation in the wild and rates exploitation as less likely. The EPSS model estimates a 3.52% probability of exploitation activity in the next 30 days, higher than 89% of all scored vulnerabilities. Microsoft released the fix on 7 April 2025 in the April 2025 Patch Tuesday, delivered through 11 security updates (KB5055519, KB5055526, KB5055523, KB5055527 and more). It affects 19 products in 2 product families (Windows, ESU).

Key facts

CVE ID: CVE-2025-27740
Severity: High CVSS 8.8
Microsoft severity: Important
Impact: Elevation of Privilege
Exploited in the wild: No
Publicly disclosed: No
Exploitation likelihood: Less Likely
Weakness: CWE-1390
EPSS: 3.52% (percentile 89%)
CISA KEV: Not listed
Released: 7 April 2025
Last updated: 9 April 2025
Patch Tuesday: April 2025 Patch Tuesday
Product families: Windows, ESU

CVSS score and vector

Microsoft scores CVE-2025-27740 at 8.8 (temporal 7.7) using CVSS 3.1. 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

Metric	Value
Attack vector	Network
Attack complexity	Low
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality impact	High
Integrity impact	High
Availability impact	High
Exploit code maturity	Unproven
Remediation level	Official fix
Report confidence	Confirmed

Description

Weak authentication in Windows Active Directory Certificate Services allows an authorized attacker to elevate privileges over a network.

Frequently asked questions (Microsoft)

How could an attacker exploit this vulnerability?

An authenticated user could manipulate attributes on computer accounts they own or manage, and acquire a certificate from Active Directory Certificate Services that would allow elevation of privilege to those of domain administrator.

Affected products (19)

Windows

Product	Security update	Type	Fixed build	Restart
Windows Server 2019	KB5055519	Security Update	10.0.17763.7136	Yes
Windows Server 2019 (Server Core installation)	KB5055519	Security Update	10.0.17763.7136	Yes
Windows Server 2022	KB5055526	Security Update	10.0.20348.3453	Yes
Windows Server 2022 (Server Core installation)	KB5055526	Security Update	10.0.20348.3453	Yes
Windows Server 2025 (Server Core installation)	KB5055523	Security Update	10.0.26100.3775	Yes
Windows Server 2022, 23H2 Edition (Server Core installation)	KB5055527	Security Update	10.0.25398.1551	Yes
Windows Server 2025	KB5055523	Security Update	10.0.26100.3775	Yes
Windows Server 2016	KB5055521	Security Update	10.0.14393.7969	Yes
Windows Server 2016 (Server Core installation)	KB5055521	Security Update	10.0.14393.7969	Yes

ESU

Product	Security update	Type	Fixed build	Restart
Windows Server 2008 for 32-bit Systems Service Pack 2	KB5055609 KB5055596	Monthly Rollup Security Only	6.0.6003.23220 6.0.6003.23220	Yes Yes
Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)	KB5055609 KB5055596	Monthly Rollup Security Only	6.0.6003.23220 6.0.6003.23220	Yes Yes
Windows Server 2008 for x64-based Systems Service Pack 2	KB5055609 KB5055596	Monthly Rollup Security Only	6.0.6003.23220 6.0.6003.23220	Yes Yes
Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)	KB5055609 KB5055596	Monthly Rollup Security Only	6.0.6003.23220 6.0.6003.23220	Yes Yes
Windows Server 2008 R2 for x64-based Systems Service Pack 1	KB5055561 KB5055570	Monthly Rollup Security Only	6.1.7601.27670 6.1.7601.27670	Yes Yes
Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)	KB5055561 KB5055570	Monthly Rollup Security Only	6.1.7601.27670 6.1.7601.27670	Yes Yes
Windows Server 2012	KB5055581	Monthly Rollup	6.2.9200.25423	Yes
Windows Server 2012 (Server Core installation)	KB5055581	Monthly Rollup	6.2.9200.25423	Yes
Windows Server 2012 R2	KB5055557	Monthly Rollup	6.3.9600.22523	Yes
Windows Server 2012 R2 (Server Core installation)	KB5055557	Monthly Rollup	6.3.9600.22523	Yes

Security updates (11)

KB5055519 (Security Update)
KB5055526 (Security Update)
KB5055523 (Security Update)
KB5055527 (Security Update)
KB5055521 (Security Update)
KB5055609 (Monthly Rollup)
KB5055596 (Security Only)
KB5055561 (Monthly Rollup)
KB5055570 (Security Only)
KB5055581 (Monthly Rollup)
KB5055557 (Monthly Rollup)

Exploitation and detection

Detection and weaponization

Weaponization maturity: Exploit.

Proof-of-concept repositories (2)

Dannners/CVE-2025-27740_POC · 1 stars
tyie949/cve-2025-27740

NIST NVD data

NVD status: Analyzed
NVD CVSS: 8.8 (HIGH)
NVD weakness: CWE-1390
Published to NVD: 8 April 2025
NVD last modified: 10 July 2025

Affected configurations (CPE)

Product	Vulnerable versions
windows server 2008 (x64)	all listed versions
windows server 2008 (x86)	all listed versions
windows server 2008 r2 (x64)	all listed versions
windows server 2012	all listed versions
windows server 2012 r2	all listed versions
windows server 2016	before 10.0.14393.7969
windows server 2019	before 10.0.17763.7136
windows server 2022	before 10.0.20348.3453
windows server 2022 23h2	before 10.0.25398.1551
windows server 2025	before 10.0.26100.3775

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-27740 (Vendor Advisory)

Acknowledgments

Konstantin Ruhmann with Volkswagen Financial Services AG

Revision history

Version	Date	Description
1.0	7 April 2025	Information published.
1.1	9 April 2025	Updated FAQ information. This is an informational change only.