Horizon Alert
Summary of the vulnerability and why it matters
A vulnerability in the Relyra SAML 2.0 Service Provider library could allow for forged authentication signatures, potentially leading to unauthorized access by bypassing signature verification. This could impact systems using the library for identity management.
- Forged signatures could bypass authentication.
- Important for systems relying on secure identity assertion.
- Confirm relevance and assess potential exposure.
Attack Path
How an attacker could exploit the issue
An attacker could forge a SAML signature to bypass authentication. This is possible because the library improperly validates the signature before confirming a successful login. By manipulating the signature, an attacker could impersonate any user.
- No authentication required.
- Forged SAML signature.
- Bypass authentication, impersonate users.
Live Threat
Current exploitation, exposure, and threat context
When supported by the advisory, a SAML 2.0 Service Provider library could accept forged SAML signatures, potentially allowing an attacker to impersonate a user and gain unauthorized access. This occurs because the library did not fully verify the cryptographic signature before issuing a successful authentication result.
- User authentication data could be at risk.
- Forged signatures may bypass verification.
- Unauthorized access to services could occur.
Operational Fix
Recommended remediation, mitigation, and detection steps
Application owners and platform teams are likely responsible for addressing this vulnerability within their Elixir and Phoenix applications. The first practical step is to identify all instances of the affected library, confirm their exposure and business criticality, and then coordinate remediation with the appropriate development teams or vendor management if a third-party product is impacted.
- Application owners should manage remediation efforts.
- Verify exposed SAML endpoints and affected applications.
- Plan for library updates during maintenance windows.
