FreePBX is an open source IP PBX. Prior to 17.0.8, the FreePBX api module's OAuth2 implementation does not sufficiently validate client credentials during token issuance. Knowledge of a valid client_id is required. The validateClient() method in ClientRepository.php unconditionally returns true, allowing any party with knowledge of a valid client_id to obtain OAuth2 access tokens without providing the correct client_secret. This vulnerability is fixed in 17.0.8.
FreePBX is an open-source web-based graphical user interface. FreePBX 15, 16, and 17 endpoints are vulnerable due to insufficiently sanitized user-supplied data allowing unauthenticated access to FreePBX Administrator leading to arbitrary database manipulation and remote code execution. This issue has been patched in endpoint versions 15.0.66, 16.0.89, and 17.0.3.