CVE-2025-66567
Published: 09 December 2025
Summary
CVE-2025-66567 is a critical-severity Improper Verification of Cryptographic Signature (CWE-347) vulnerability in Onelogin Ruby-Saml. Its CVSS base score is 9.3 (Critical).
Operationally, ranked at the 16.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-201812
Vulnerability details
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…
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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.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Requires verification of digital signatures using organization-approved certificates before installation, directly preventing improper verification of cryptographic signatures.
Component authenticity commonly depends on cryptographic signatures; the control enforces proper verification of those signatures.
PKI certificates under an approved policy require cryptographic signature verification on issuance and validation.
Requires cryptographic signatures on authoritative data and support for verifying the chain of trust.
Mandates verification of cryptographic signatures (e.g., DNSSEC RRSIG) on resolution responses, addressing missing or bypassed signature checks.
Integrity tools commonly rely on cryptographic signatures whose improper validation this weakness covers.
Authenticity validation commonly relies on cryptographic signature or certificate checks that this control enforces.