The Registration & Login with Mobile Phone Number for WooCommerce plugin for WordPress is vulnerable to Authentication Bypass in all versions up to, and including, 1.3.1. This is due to the plugin not properly verifying a users identity prior to authenticating them via the fma_lwp_set_session_php_fun() function. This makes it possible for unauthenticated attackers to authenticate as any user on the site, including administrators, without a valid password.