CVE-2025-66567NVD

Vulnerability Summary

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.

Severity Level

CRITICAL(9.3)

Published Date

Dec 9, 2025

Last Modified

Dec 9, 2025

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

Data Pending

Root Weakness (CWE)

CWE-347: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v4.0 Base Metrics — Score 9.3 (CRITICAL)

Attack VectorNetwork

Attack ComplexityLow

Attack RequirementsNone

Privileges RequiredNone

User InteractionNone

Confidentiality (Vulnerable System)High

Integrity (Vulnerable System)High

Availability (Vulnerable System)None

Confidentiality (Subsequent System)None

Integrity (Subsequent System)None

Availability (Subsequent System)None

Affected & Patched Versions

Affected Versions

Not provided by NVD for this CVE.

Patched Versions

Not provided by NVD for this CVE.

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