Customer Email Verification for WooCommerce <= 2.8.2 - Unauthenticated Authentication Bypass via Predictable Email-Verification Token to 'cusomer_email_verify' Parameter

The Customer Email Verification for WooCommerce plugin for WordPress is vulnerable to Authentication Bypass via a Predictable Email-Verification Token in all versions up to, and including, 2.8.2. This is due to the authenticate_user_by_email_link() function — hooked on the wp action and triggered by the cusomer_email_verify GET parameter — lacking any capability check or nonce verification, while the secret_code it validates is generated as md5(email . time()) and the verify_otp_nonce required to trigger token issuance via the wp_ajax_nopriv_resend_otp handler is emitted to every front-end visitor through wp_localize_script. This makes it possible for unauthenticated attackers to log in as a newly created, verified WooCommerce customer bound to an arbitrary email address — or to flip an existing account's customer_email_verified meta to verified — fully bypassing the plugin's core email-verification control. Exploitation requires the cev_user_log table to contain a password column, which is absent from the fresh-install schema shipped in version 2.8.2 but is present on sites upgraded from an older version where that column was defined.