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 contain a patch for the issue.
Weakness
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Omniauth_saml | Omniauth | * | 1.10.6 (excluding) |
| Omniauth_saml | Omniauth | 2.0.0 (including) | 2.1.3 (excluding) |
| Omniauth_saml | Omniauth | 2.2.0 (including) | 2.2.3 (excluding) |
| Ruby-saml | Onelogin | * | 1.12.4 (excluding) |
| Ruby-saml | Onelogin | 1.13.0 (including) | 1.18.0 (excluding) |
| Ruby-saml | Ubuntu | esm-apps/bionic | * |
| Ruby-saml | Ubuntu | esm-apps/focal | * |
| Ruby-saml | Ubuntu | esm-apps/jammy | * |
| Ruby-saml | Ubuntu | esm-apps/noble | * |
| Ruby-saml | Ubuntu | esm-apps/xenial | * |
| Ruby-saml | Ubuntu | focal | * |
| Ruby-saml | Ubuntu | jammy | * |
| Ruby-saml | Ubuntu | noble | * |
| Ruby-saml | Ubuntu | oracular | * |
| Ruby-saml | Ubuntu | plucky | * |
| Ruby-saml | Ubuntu | upstream | * |
Related Attack Patterns
References
- https://about.gitlab.com/releases/2025/03/12/patch-release-gitlab-17-9-2-released
- https://github.blog/security/sign-in-as-anyone-bypassing-saml-sso-authentication-with-parser-differentials
- https://github.com/SAML-Toolkits/ruby-saml/commit/e76c5b36bac40aedbf1ba7ffaaf495be63328cd9
- https://github.com/SAML-Toolkits/ruby-saml/commit/e9c1cdbd0f9afa467b585de279db0cbd0fb8ae97
- https://github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.12.4
- https://github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.18.0
- https://github.com/SAML-Toolkits/ruby-saml/security/advisories/GHSA-754f-8gm6-c4r2
- https://github.com/omniauth/omniauth-saml/security/advisories/GHSA-hw46-3hmr-x9xv
- https://portswigger.net/research/saml-roulette-the-hacker-always-wins
- https://securitylab.github.com/advisories/GHSL-2024-329_GHSL-2024-330_ruby-saml
- https://lists.debian.org/debian-lts-announce/2025/04/msg00011.html
- https://news.ycombinator.com/item?id=43374519
- https://security.netapp.com/advisory/ntap-20250314-0009/