CoreWCF up to 1.8.0/1.9.0 SAML Token Replay Cache TryAdd authentication replay

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in CoreWCF up to 1.8.0/1.9.0. This impacts the function TryAdd of the component SAML Token Replay Cache. Executing a manipulation can lead to authentication replay. This vulnerability is handled as CVE-2026-54779. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as critical was found in CoreWCF up to 1.8.0/1.9.0. This vulnerability affects the function TryAdd of the component SAML Token Replay Cache. The manipulation with an unknown input leads to a authentication replay vulnerability. The CWE definition for the vulnerability is CWE-294. A capture-replay flaw exists when the design of the product makes it possible for a malicious user to sniff network traffic and bypass authentication by replaying it to the server in question to the same effect as the original message (or with minor changes). As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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, CoreWCF SAML token replay protection is inoperative because DefaultTokenReplayCache.TryAdd does not reject duplicate tokens when DetectReplayedTokens is enabled, allowing a captured token to be reused. This issue is fixed in versions 1.8.1 and 1.9.1.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-54779 since 06/16/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1040.

Upgrading to version 1.8.1 or 1.9.1 eliminates this vulnerability.

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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: Authentication replay
CWE: CWE-294 / CWE-287
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-2026-54779 (🔒)
GCVE (CVE): GCVE-0-2026-54779
GCVE (VulDB): GCVE-100-377056

Entryinfo

Created: 07/09/2026 00:52
Changes: 07/09/2026 00:52 (53)
Complete: 🔍
Cache ID: 216::103

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