CVE-2025-66567: Ruby-saml has a SAML authentication bypass due to namespace handling (parser differential)
(updated )
Ruby-saml up to and including 1.12.4, there is an authentication bypass vulnerability because of an incomplete fix for CVE-2025-25292. ReXML and Nokogiri parse XML differently, the parsers can generate entirely different document structures from the same XML input. That allows an attacker to be able to execute a Signature Wrapping attack. The vulnerability does not affect the version 1.18.0.
References
- github.com/SAML-Toolkits/ruby-saml
- github.com/SAML-Toolkits/ruby-saml/commit/e9c1cdbd0f9afa467b585de279db0cbd0fb8ae97
- github.com/SAML-Toolkits/ruby-saml/security/advisories/GHSA-9v8j-x534-2fx3
- github.com/advisories/GHSA-754f-8gm6-c4r2
- github.com/advisories/GHSA-9v8j-x534-2fx3
- github.com/rubysec/ruby-advisory-db/blob/master/gems/ruby-saml/CVE-2025-66567.yml
- nvd.nist.gov/vuln/detail/CVE-2025-66567
Code Behaviors & Features
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