Vulnerability record · CVE-2025-66567 · published 9 December 2025

CVE-2025-66567: Onelogin ruby-saml improper verification of cryptographic signature vulnerability

Onelogin · Ruby Saml

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.

9.3 CVSS 4.0 Critical EPSS 0.39% · top 69.3% CWE-347 · Improper verification of cryptographic signature

9.3CVSS 4.0 base score

0.39%EPSS exploitation probability, 30 days

NoNot in CISA KEV

1Affected product versions listed by NVD

3References

17 Jun 2026Last modified by NVD

Description

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:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

Ruby Saml Onelogin

References

Link	Tags
https://github.com/SAML-Toolkits/ruby-saml/commit/e9c1cdbd0f9afa467b585de279db0cbd0fb8ae97	Patch
https://github.com/SAML-Toolkits/ruby-saml/security/advisories/GHSA-9v8j-x534-2fx3	Vendor Advisory
https://github.com/advisories/GHSA-754f-8gm6-c4r2	Not Applicable

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2024-45409Onelogin ruby-saml improper verification of cryptographic signature vulnerabilityThe Ruby SAML library is for implementing the client side of a SAML authorization. Ruby-SAML in <= 12.2 and 1.13.0 <= 1.16.0 does not properly verify…EPSS 11%10 Sep 2024 9.8CVE-2015-20108Onelogin ruby-saml command injection vulnerabilityxml_security.rb in the ruby-saml gem before 1.0.0 for Ruby allows XPath injection and code execution because prepared statements are not used.EPSS 1.3%27 May 2023 9.8CVE-2017-11428Onelogin ruby-saml improper authentication vulnerabilityOneLogin Ruby-SAML 1.6.0 and earlier may incorrectly utilize the results of XML DOM traversal and canonicalization APIs in such a way that an attacke…EPSS 2.4%17 Apr 2019 9.3CVE-2025-66568Onelogin ruby-saml improper verification of cryptographic signature vulnerabilityThe ruby-saml library implements the client side of an SAML authorization. Versions up to and including 1.12.4, are vulnerable to authentication bypa…EPSS 0.23%9 Dec 2025 9.3CVE-2025-25291Omniauth saml improper verification of cryptographic signature vulnerabilityruby-saml provides security assertion markup language (SAML) single sign-on (SSO) for Ruby. An authentication bypass vulnerability was found in ruby-…EPSS 21%12 Mar 2025 9.3CVE-2025-25292ruby-saml parser differential enables SAML signature wrapping auth bypassruby-saml before 1.12.4 and 1.18.0 is vulnerable to an authentication bypass caused by a parser differential between ReXML and Nokogiri, which can pr…EPSS 65%analysed12 Mar 2025 7.7CVE-2025-25293Omniauth saml uncontrolled resource consumption vulnerabilityruby-saml provides security assertion markup language (SAML) single sign-on (SSO) for Ruby. Prior to versions 1.12.4 and 1.18.0, ruby-saml is suscept…EPSS 1.5%12 Mar 2025 7.5CVE-2016-5697Onelogin ruby-saml xml injection vulnerabilityRuby-saml before 1.3.0 allows attackers to perform XML signature wrapping attacks via unspecified vectors.EPSS 1.2%23 Jan 2017

Source: NIST National Vulnerability Database (record CVE-2025-66567), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.