5.9
MEDIUM CVSS 3.1
CVE-2026-54779
CoreWCF: SAML token replay protection is inoperative
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.

INFO

Published Date :

July 8, 2026, 11:16 p.m.

Last Modified :

July 8, 2026, 11:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-54779 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update CoreWCF to version 1.8.1 or later to fix SAML token replay issues.
  • Update CoreWCF to version 1.8.1 or later.
  • Ensure SAML token replay protection is enabled.
  • Verify token uniqueness handling.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-54779 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-54779 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-54779 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 08, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'CoreWCF', 'product': 'CoreWCF', 'versions': [{'status': 'affected', 'version': '>= 1.9.0, < 1.9.1'}, {'status': 'affected', 'version': '< 1.8.1'}]}]
    Added 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.
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
    Added CWE CWE-613
    Added CWE CWE-294
    Added Reference https://github.com/CoreWCF/CoreWCF/commit/3800c4e2bb4c6fde00ddacefdc2221ef33d55621
    Added Reference https://github.com/CoreWCF/CoreWCF/commit/7b0b5231cf21b4b5c1fc3caac9981f8bee43823f
    Added Reference https://github.com/CoreWCF/CoreWCF/commit/84f8cff5a786b5aaa73448cb379d366a7df98238
    Added Reference https://github.com/CoreWCF/CoreWCF/releases/tag/v1.8.1
    Added Reference https://github.com/CoreWCF/CoreWCF/releases/tag/v1.9.1
    Added Reference https://github.com/CoreWCF/CoreWCF/security/advisories/GHSA-9jr3-rj99-8jq3
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.