A high-severity authorization bypass vulnerability in EasyCorp EasyAdminBundle allows authenticated users to access restricted functionality by manipulating route parameters.

The application fails to validate the routeName parameter during the kernel.controller event, which occurs after the initial security firewall check. This allows a low-privilege authenticated user to bypass path-based access controls and execute restricted controller actions.

Successful exploitation allows an authenticated user to perform unauthorized actions within the administrative backend, potentially leading to unauthorized data access or modification. With a CVSS score of 8.1, this vulnerability poses a significant risk to the integrity and confidentiality of the application, as it effectively nullifies configured path-based security rules.

Immediate Action: Upgrade EasyAdminBundle to version 4.29.16 or 5.5.1 immediately to implement proper route validation.

Proactive Monitoring: Review application access logs for unusual requests targeting administrative routes or unexpected controller execution patterns.

Compensating Controls: Ensure that sensitive controllers utilize internal authorization checks, such as the Symfony #[IsGranted] attribute or denyAccessUnlessGranted() calls, as these mechanisms are not bypassed by this flaw.

Public Exploit Available: Unknown

Given the potential for unauthorized administrative access, administrators should prioritize updating EasyAdminBundle to the specified patched versions. Organizations relying on path-based security rules for access control should verify that these configurations are supplemented by controller-level authorization checks to provide defense-in-depth against this class of vulnerability.