The WooCommerce OTP Login With Phone Number, OTP Verification plugin for WordPress is vulnerable to authentication bypass due to insufficient empty value checking in the lwp_ajax_register function in all versions up to, and including, 1.8.47. This makes it possible for unauthenticated attackers to bypass OTP verification and gain administrative access to any user account with a configured phone number by exploiting improper Firebase API error handling when the Firebase API key is not configured.