CVE-2025-47949: 
JavaScript vulnerability analysis and mitigation

CVE-2025-47949 is a critical Signature Wrapping vulnerability affecting samlify, a Node.js library for SAML single sign-on, discovered in versions prior to 2.10.0. The vulnerability was disclosed on May 19, 2025, and received a CVSS v4.0 score of 9.9 (Critical). Samlify is widely used in enterprise applications with approximately 768,000 downloads per month, making this vulnerability particularly significant for organizations implementing SAML-based authentication (Wiz, NVD).

The vulnerability stems from improper verification of cryptographic signatures (CWE-347) in the SAML authentication process. The flaw allows attackers to manipulate signed SAML responses by injecting unsigned assertions while maintaining a valid signature from the identity provider. The attack exploits flaws in how the samlify library parses and verifies SAML responses, specifically in the signature validation logic. An attacker would need a signed XML document by the identity provider to execute the attack (SOCRadar, Bleeping Computer).

The vulnerability enables attackers to bypass authentication controls completely and impersonate any user in the system, including administrators. This could lead to unauthorized access to sensitive systems, privilege escalation, and lateral movement within enterprise environments. Given the library's widespread use in enterprise-grade authentication systems, particularly in SaaS platforms and organizations implementing SSO for internal tools, the potential impact is significant (SOCRadar, Wiz).

Organizations using samlify are strongly advised to upgrade immediately to version 2.10.0 or later, which includes fixes for this vulnerability. Additional recommended mitigation steps include reviewing and securing SSO flows, ensuring HTTPS is enforced, avoiding the use of untrusted or intercepted SAML responses, and monitoring systems for signs of unauthorized access (SOCRadar, GitHub Advisory).

The disclosure of CVE-2025-47949 has sent ripples through the Node.js developer community, particularly due to its critical severity and the widespread use of the affected library. The vulnerability has drawn significant attention from security researchers and organizations, emphasizing the importance of proper cryptographic signature verification in authentication systems (SOCRadar).