Improper verification of cryptographic signature in SAML SSO for Ruby - CVE-2025-66568
Published: December 9, 2025
Vulnerability identifier: #VU119404
CSH Severity: High
CVSS v4.0: 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:U/U:Amber
CVE-ID: CVE-2025-66568
CWE-ID: CWE-347
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: SAML-Toolkits
Affected software:
SAML SSO for Ruby
SAML SSO for Ruby
Detailed vulnerability description
The vulnerability allows a remote attacker to bypass authentication.
The vulnerability exists due to a libxml2 canonicalization error when handling invalid XML input. A remote attacker can supply specially crafted XML data to the application and execute a Signature Wrapping attack, leading to authentication bypass.
How to mitigate CVE-2025-66568
Install updates from vendor's website.