CVE-2026-54779 | BDVDB-2026-346240 Detail

CoreWCFCoreWCF

Description#

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.

Impact#

Per CVSS v3.1: confidentiality impact none, integrity impact high, availability impact none. Attack vector: network.

Weaknesses#

CWE-294 Authentication Bypass by Capture-replay
CWE-613 Insufficient Session Expiration

References#

Exploit#

No public exploit known

History#

Version 12026-07-08Record published in the CVE List.
Version 22026-07-09Most recent update recorded in the CVE List.

Published

Published: 2026-07-08
Last modified: 2026-07-09

Vendor information

Vendor: CoreWCF
Product: CoreWCF

All CoreWCF vulnerabilities

Score

5.9 Medium

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 38.0.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Authentication Issues

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
>= 1.9.0, < 1.9.1
Fixed
Not stated
Vulnerable
< 1.8.1
Fixed
Not stated

Scoring System

CVSS v4.0

Not available

CVSS v3.1

5.9 Medium

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Metric breakdown
Attack Vector	Network
Attack Complexity	High
Privileges Required	None
User Interaction	None
Scope	Unchanged
Confidentiality	None
Integrity	High
Availability	None

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).