Keyfactor SignServer up to 7.1 Container Startup certificate validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Keyfactor SignServer up to 7.1. The affected element is an unknown function of the component Container Startup. Performing a manipulation results in certificate validation. This vulnerability is identified as CVE-2025-26787. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Keyfactor SignServer up to 7.1. This affects an unknown code of the component Container Startup. The manipulation with an unknown input leads to a certificate validation vulnerability. CWE is classifying the issue as CWE-295. The product does not validate, or incorrectly validates, a certificate. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

An error in the SignServer container startup logic was found in Keyfactor SignServer versions prior to 7.2. The Admin CLI command used to configure Certificate access to the initial startup of the container sets a property of "allowany" to allow any user with a valid and trusted client auth certificate to connect. Admins can then set more restricted access to specific certificates. A logic error caused this admin CLI command to be run on each restart of the container instead of only the first startup as intended resetting the configuration to "allowany".

The advisory is shared at support.keyfactor.com. This vulnerability is uniquely identified as CVE-2025-26787 since 02/14/2025. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1587.003 for this issue.

Upgrading to version 7.2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-204738). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.6
VulDB Temp Score: 5.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Certificate validation
CWE: CWE-295 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: SignServer 7.2

Timelineinfo

02/14/2025 CVE reserved
12/22/2025 +311 days Advisory disclosed
12/22/2025 +0 days VulDB entry created
12/22/2025 +0 days VulDB entry last update

Sourcesinfo

Advisory: support.keyfactor.com
Status: Confirmed

CVE: CVE-2025-26787 (🔒)
GCVE (CVE): GCVE-0-2025-26787
GCVE (VulDB): GCVE-100-337761
EUVD: 🔒

Entryinfo

Created: 12/22/2025 19:40
Updated: 12/22/2025 20:21
Changes: 12/22/2025 19:40 (55), 12/22/2025 20:21 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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