CVE-2025-27740Network attack vector

Authenticated privilege escalation via weak certificate authentication

Published Apr 8, 2025 · Updated Aug 10, 2026

Weak authentication in Microsoft Windows Active Directory Certificate Services allows remote authenticated users to elevate privileges over a network. Microsoft has not published the affected function or the exact authentication operation that mishandles attacker-controlled input. A low-privileged account and network access are required, and successful exploitation grants elevated Windows privileges.

CVSS severity8.8
High
EPSS probability3.42%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Weak authentication in Microsoft Windows Active Directory Certificate Services allows remote authenticated users to elevate privileges over a network. Microsoft has not published the affected function or the exact authentication operation that mishandles attacker-controlled input. A low-privileged account and network access are required, and successful exploitation grants elevated Windows privileges.

The record

CVE
CVE-2025-27740
Published
Apr 8, 2025
Updated
Aug 10, 2026
Vendor
Microsoft
Product
Windows Server 2019
Classifications
CWE-1390
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 8, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=10.0.17763.0 <10.0.17763.7136

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Microsoft · Windows Server 2019version=10.0.17763.0 <10.0.17763.7136
Microsoft · Windows Server 2025 (Server Core installation)version=10.0.26100.0 <10.0.26100.3775
Microsoft · Windows Server 2016 (Server Core installation)version=10.0.14393.0 <10.0.14393.7969
Microsoft · Windows Server 2012 (Server Core installation)version=6.2.9200.0 <6.2.9200.25423
Microsoft · Windows Server 2012version=6.2.9200.0 <6.2.9200.25423
Microsoft · Windows Server 2022, 23H2 Edition (Server Core installation)version=10.0.25398.0 <10.0.25398.1551
Microsoft · Windows Server 2016version=10.0.14393.0 <10.0.14393.7969
Microsoft · Windows Server 2008 R2 Service Pack 1version=6.1.7601.0 <6.1.7601.27670
Microsoft · Windows Server 2008 R2 Service Pack 1 (Server Core installation)version=6.1.7601.0 <6.1.7601.27670
Microsoft · Windows Server 2012 R2 (Server Core installation)version=6.3.9600.0 <6.3.9600.22523
Microsoft · Windows Server 2019 (Server Core installation)version=10.0.17763.0 <10.0.17763.7136
Microsoft · Windows Server 2008 Service Pack 2version=6.0.6003.0 <6.0.6003.23220
Microsoft · Windows Server 2022version=10.0.20348.0 <10.0.20348.3453
Microsoft · Windows Server 2025version=10.0.26100.0 <10.0.26100.3775
Microsoft · Windows Server 2012 R2version=6.3.9600.0 <6.3.9600.22523
Microsoft · Windows Server 2008 Service Pack 2 (Server Core installation)version=6.0.6003.0 <6.0.6003.23220

Published CVSS scores

8.8Microsoft CorporationCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1390Weak Authentication

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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