CVE-2025-66567
ruby-saml has a SAML authentication bypass due to namespace handling (parser differential)
- State
- Published
- Severity
- 9.3 Critical
- Published
- Dec 9, 2025
- Updated
- Dec 9, 2025
- Reserved
- Dec 4, 2025
Description
The ruby-saml library is for implementing the client side of a SAML authorization. ruby-saml versions up to and including 1.12.4 contain an authentication bypass vulnerability due to an incomplete fix for CVE-2025-25292. ReXML and Nokogiri parse XML differently, generating entirely different document structures from the same input. This allows an attacker to execute a Signature Wrapping attack. This issue is fixed in version 1.18.0.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 9.3 Critical | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N | GitHub_M |
Weaknesses
- CWE-347 Improper Verification of Cryptographic Signature
Affected Products
| Product | Versions |
|---|---|
ruby-samlSAML-Toolkits |
|
References
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