The WP Directorybox Manager plugin for WordPress is vulnerable to authentication bypass in versions up to, and including, 2.5. This is due to incorrect authentication in the wp_dp_enquiry_agent_contact_form_submit_callback function. This makes it possible for unauthenticated attackers to log in as any existing user on the site, such as an administrator, if they have access to the username.
The product requires authentication, but the product has an alternate path or channel that does not require authentication.