SSL Wireless SMS Notification <= 3.8.1 - Unauthenticated Authentication Bypass to Account Takeover

SSL Wireless SMS Notification for WordPress is vulnerable to Authentication Bypass in all versions up to, and including, 3.8.1. The public final_login_ajax_action handler resolves a user and issues an authenticated session by matching the wp_sslcare_otp table on only the attacker-supplied phone and cap_data, without verifying the SMS OTP or any server-side single-use state. Because cap_data was chosen by the attacker in the public otp_login_ajax_action step (which stores the row before sending the SMS), the finalize step trivially matches and the user is looked up solely by the sslcare_login_phone meta. This makes it possible for unauthenticated attackers who know a phone-linked user's number to take over that account.