CVE-2022-23505 is a security vulnerability classified under CWE-287 (Improper Authentication) affecting the 'passport-wsfed-saml2' library, a Node.js authentication provider implementing WS-Federation and SAML2 token authentication for the Passport framework. Versions prior to 4.6.3 of this library are vulnerable to an authentication bypass attack. The vulnerability arises because the library improperly validates WS-Federation authentication tokens, allowing a remote attacker who possesses an arbitrary Identity Provider (IDP) signed assertion to bypass authentication controls on websites using this library. In some cases, depending on the IDP configuration, attackers may be able to generate signed assertions without any valid user credentials, enabling fully unauthenticated access. This flaw compromises the authentication mechanism, potentially allowing unauthorized access to protected resources. The issue was addressed and patched in version 4.6.3 of passport-wsfed-saml2. As a workaround, switching to SAML2 authentication instead of WS-Federation can mitigate the risk. No known exploits have been reported in the wild to date. The vulnerability impacts the confidentiality and integrity of authentication processes and can lead to unauthorized access if exploited. The attack requires possession or generation of a signed assertion, which may vary in difficulty depending on the IDP setup. No user interaction is required once the attacker has a valid assertion, and the scope includes any web applications relying on vulnerable versions of passport-wsfed-saml2 for WS-Federation authentication.

For European organizations, this vulnerability poses a significant risk to web applications that use the passport-wsfed-saml2 library for WS-Federation authentication. Unauthorized access could lead to exposure of sensitive data, unauthorized transactions, and potential lateral movement within corporate networks. Sectors such as finance, government, healthcare, and critical infrastructure that rely on federated authentication for single sign-on (SSO) are particularly at risk. Exploitation could undermine trust in identity management systems and lead to regulatory non-compliance under GDPR due to unauthorized data access. The impact extends to service availability if attackers leverage unauthorized access to disrupt services. Given the reliance on federated identity providers in European enterprises, the vulnerability could facilitate sophisticated attacks targeting high-value assets and confidential information.

European organizations should immediately audit their use of the passport-wsfed-saml2 library and upgrade all instances to version 4.6.3 or later to apply the official patch. Where upgrading is not immediately feasible, switching authentication protocols from WS-Federation to SAML2 is a practical interim mitigation. Organizations should review and harden their Identity Provider configurations to restrict the generation of signed assertions, ensuring strict validation and limiting assertion issuance to authorized users only. Implementing additional layers of authentication, such as multi-factor authentication (MFA), can reduce the risk of unauthorized access even if assertion validation is bypassed. Regularly monitoring authentication logs for anomalous assertion usage and failed authentication attempts can help detect exploitation attempts early. Security teams should also validate that their federated authentication flows include robust signature verification and timestamp checks to prevent replay attacks. Finally, organizations should engage with their software vendors and identity providers to ensure timely updates and security best practices are followed.