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.

Classification

CVE ID: CVE-2025-25291

CVSS Base Severity: HIGH

CVSS Base Score: 8.0

CVSS Vector: 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/E:U

Affected Products

Vendor: SAML-Toolkits

Product: ruby-saml

Exploit Prediction Scoring System (EPSS)

EPSS Score: 1.11% (probability of being exploited)

EPSS Percentile: 76.33% (scored less or equal to compared to others)

EPSS Date: 2025-04-10 (when was this score calculated)

Stakeholder-Specific Vulnerability Categorization (SSVC)

SSVC Exploitation: none

SSVC Technical Impact: partial

SSVC Automatable: true

References

https://nvd.nist.gov/vuln/detail/CVE-2025-25291
https://github.com/SAML-Toolkits/ruby-saml/security/advisories/GHSA-4vc4-m8qh-g8jm
https://github.com/omniauth/omniauth-saml/security/advisories/GHSA-hw46-3hmr-x9xv
https://github.com/SAML-Toolkits/ruby-saml/commit/e76c5b36bac40aedbf1ba7ffaaf495be63328cd9
https://github.com/SAML-Toolkits/ruby-saml/commit/e9c1cdbd0f9afa467b585de279db0cbd0fb8ae97
https://about.gitlab.com/releases/2025/03/12/patch-release-gitlab-17-9-2-released
https://github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.12.4
https://github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.18.0

Timeline