CVE-2026-49454

Relyra SAML SignatureValue not cryptographically verified -> authentication bypass

State
Published
Severity
9.1 Critical
Published
Jun 18, 2026
Updated
Jun 22, 2026
Reserved
May 30, 2026

Read the record on cve.org

Description

Relyra is a strict-by-default SAML 2.0 Service Provider library for Elixir and Phoenix. Versions 1.0.0 and 1.1.0 accept forged SAML signatures because SignatureValue was not cryptographically verified before the library returned a successful authentication result. The XMLDSig trust boundary was incomplete as :public_key.verify over the exclusive-C14N canonicalized SignedInfo was not performed against the configured IdP certificate's public key, DigestValue was not recomputed over the canonicalized referenced element, and canonicalize/2 remained an unused passthrough in the signature-verification path. The result was a structure-only acceptance path where document shape and trust-source rejection could succeed without proving the signature bytes. A forged SignatureValue carrying an attacker-controlled NameID could be accepted as {:ok}. This issue has been fixed in version 1.2.0.

Scores

CVSSScoreVectorSource
3.19.1 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NGitHub_M

Weaknesses

  • CWE-287 Improper Authentication
  • CWE-347 Improper Verification of Cryptographic Signature

Affected Products

ProductVersions
relyraszTheory
  • >= 1.0.0, < 1.2.0Affected

References

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