CVE-2025-25291: ruby-saml vulnerable to SAML authentication bypass due to DOCTYPE handling (parser differential)
Description
ruby-saml provides security assertion markup language (SAML) single sign-on (SSO) for Ruby. An authentication bypass vulnerability was found in ruby-saml prior to versions 1.12.4 and 1.18.0 due to a parser differential. 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. This issue may lead to authentication bypass. Versions 1.12.4 and 1.18.0 fix the issue.
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H · CWE-347, CWE-436
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
SAML-Toolkits: ruby-saml
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- about.gitlab.com/releases/2025/03/12/patch-release-gitlab-17-9-2-released (opens in new tab)
- github.blog/security/sign-in-as-anyone-bypassing-saml-sso-authentication-with-par… (opens in new tab)
- github.com/omniauth/omniauth-saml/security/advisories/GHSA-hw46-3hmr-x9xv (opens in new tab)
- github.com/SAML-Toolkits/ruby-saml/commit/e76c5b36bac40aedbf1ba7ffaaf495be63328c… (opens in new tab)
- github.com/SAML-Toolkits/ruby-saml/commit/e9c1cdbd0f9afa467b585de279db0cbd0fb8ae… (opens in new tab)
- github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.12.4 (opens in new tab)
- github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.18.0 (opens in new tab)
- github.com/SAML-Toolkits/ruby-saml/security/advisories/GHSA-4vc4-m8qh-g8jm (opens in new tab)
- portswigger.net/research/saml-roulette-the-hacker-always-wins (opens in new tab)
- securitylab.github.com/advisories/GHSL-2024-329_GHSL-2024-330_ruby-saml (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)