Authentication bypass in Customer Email Verification for WooCommerce

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.