VYPR
Critical severity10.0NVD Advisory· Published Jun 19, 2026· Updated Jun 19, 2026

CoreWCF: Authentication bypass in CoreWCF SAML 1.1 / 2.0 token signature validation

CVE-2026-54782

Description

Impact

Full impersonation of any principal the trusted STS could have issued an assertion for — including administrative principals when the relying party grants them via SAML claims. Affects both SAML 1.1 and SAML 2.0.

Preconditions

Relying-party service is hosted with WSFederationHttpBinding or WS2007FederationHttpBinding (or any binding that triggers FederatedSecurityTokenManager for issued-token validation), and IdentityConfiguration is wired (UseIdentityConfiguration = true). Attacker can reach the service over the network and knows the trusted STS’s public certificate (public certs are by design discoverable).

Patches

Fixed in CoreWCF v1.8.1 and v1.9.1

Workarounds

None

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

Affected products

1

Patches

Vulnerability mechanics

No source-code context for this CVE — mechanics is only generated when we can read the actual fix diff. Without that, the four sections (root cause, attack vector, affected code, fix) would be speculation rather than analysis.

References

2

News mentions

0

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