CVE-2026-49454 Relyra SAML SignatureValue not cryptographically verified -> authentication bypass
Attackers can bypass authentication in Relyra SAML library by forging signatures, allowing unauthorized access and account takeover.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-49454?
CVE-2026-49454 is a critical authentication bypass vulnerability in szTheory relyra, published on 18 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Which versions are affected by CVE-2026-49454?
2 open source packages ship an affected version, including relyra.
| Package | Affected | Fixed in |
|---|---|---|
relyra Hex | From 1.0.0 | 1.2.0 |
relyra Hex | From 1.0.0 | 1.2.0 |
How do I fix CVE-2026-49454?
Upgrade relyra to 1.2.0 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-49454 being exploited?
There is no known exploitation of CVE-2026-49454 in the wild and no public exploit code.
Sources
Also known as GHSA-jv46-xfwm-36j7.