CoreWCF up to 1.8.0/1.9.0 SamlSerializer signature verification

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in CoreWCF up to 1.8.0/1.9.0. Affected is an unknown function of the component SamlSerializer. The manipulation leads to signature verification. This vulnerability is uniquely identified as CVE-2026-54774. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability, which was classified as critical, has been found in CoreWCF up to 1.8.0/1.9.0. This issue affects some unknown functionality of the component SamlSerializer. The manipulation with an unknown input leads to a signature verification vulnerability. Using CWE to declare the problem leads to CWE-347. The product does not verify, or incorrectly verifies, the cryptographic signature for data. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. Prior to 1.8.1 and 1.9.1, SamlSerializer skips final SignatureValue verification when a CoreWCF service validates SAML tokens using a non-X.509 signing token, allowing an attacker to reference a non-X.509 SecurityToken key identifier and bypass assertion signature verification. This issue is fixed in versions 1.8.1 and 1.9.1.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-54774 since 06/16/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available.

Upgrading to version 1.8.1 or 1.9.1 eliminates this vulnerability.

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

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Signature verification
CWE: CWE-347 / CWE-345
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: CoreWCF 1.8.1/1.9.1

Timelineinfo

06/16/2026 CVE reserved
07/08/2026 +22 days VulDB entry created
07/09/2026 +0 days Advisory disclosed
07/09/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-54774 (🔒)
GCVE (CVE): GCVE-0-2026-54774
GCVE (VulDB): GCVE-100-377057

Entryinfo

Created: 07/09/2026 00:54
Changes: 07/09/2026 00:54 (52)
Complete: 🔍
Cache ID: 216::103

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

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