CVE-2026-54779
Medium
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.
SeverityMedium
CVSS5.9
Exploit probability—
ProductCorewcf.primitives
PublishedJul 8, 2026
First seenJul 8, 2026
Weakness typeCWE-294CWE-294CWE-613CWE-613
How to fix
Update
- CoreWCF.Primitives1.8.1, 1.9.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| CoreWCF.PrimitivesNuGet | v < 1.8.1, 1.9.0 ≤ v < 1.9.1 | 1.8.1, 1.9.1 |
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