CVE-2025-25291
An authentication bypass vulnerability was found in ruby-saml prior to versions 1.12.4 and 1.18.0 due to a parser differential.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 20.6%, higher than 97% of all known CVEs. Patch or mitigate before the next change window.
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.
- CVSS 4.0
- 9.3 CRITICALCVSS: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:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 20.59% probability · 97th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-347, CWE-436
- Affected
- omniauth/omniauth saml · onelogin/ruby-saml · netapp/storagegrid
- Source
- security-advisories@github.com
References
- https://about.gitlab.com/releases/2025/03/12/patch-release-gitlab-17-9-2-releasedPatch
- https://github.blog/security/sign-in-as-anyone-bypassing-saml-sso-authentication-with-parser-differentialsExploit, Third Party Advisory
- https://github.com/SAML-Toolkits/ruby-saml/commit/e76c5b36bac40aedbf1ba7ffaaf495be63328cd9Patch
- https://github.com/SAML-Toolkits/ruby-saml/commit/e9c1cdbd0f9afa467b585de279db0cbd0fb8ae97Patch
- https://github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.12.4Release Notes
- https://github.com/SAML-Toolkits/ruby-saml/releases/tag/v1.18.0Release Notes
- https://github.com/SAML-Toolkits/ruby-saml/security/advisories/GHSA-4vc4-m8qh-g8jmVendor Advisory
- https://github.com/omniauth/omniauth-saml/security/advisories/GHSA-hw46-3hmr-x9xvVendor Advisory
- https://portswigger.net/research/saml-roulette-the-hacker-always-winsExploit, Third Party Advisory
- https://securitylab.github.com/advisories/GHSL-2024-329_GHSL-2024-330_ruby-samlThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2025/04/msg00011.html
- https://news.ycombinator.com/item?id=43374519Issue Tracking
- https://security.netapp.com/advisory/ntap-20250314-0010/Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.