by Kastro
Paper/Archive/CVE-2025-66567

CVE-2025-66567

SAML-Toolkits ruby-saml — ruby-saml has a SAML authentication bypass due to namespace handling (parser differential)

EPSS 0.4%CVSS 9.3
critical.is priorityof 100
35
CVSS 9.3 (CNA)9.3 / 10 × 3027.9Not in CISA KEV+300.0EPSS percentile 35.9.359 × 207.2No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
ruby-saml< 1.18.0–CNA

Scores by source

GitHub_M (CNA)9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
NVD9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refgithub.com/SAML-Toolkits/ruby-saml/security/advisories/GHSA-9v8j-x534-2fx3refgithub.com/SAML-Toolkits/ruby-saml/commit/e9c1cdbd0f9afa467b585de279db0cbd0fb8ae97refgithub.com/advisories/GHSA-754f-8gm6-c4r2