DescriptionWooCommerce PayPal Pro Payment Gateway plugin before 4.1.1 contains an unauthenticated payment bypass vulnerability that allows remote attackers to mark unpaid orders as paid by exploiting the pp_capture_order AJAX handler, which is gated only by a public checkout nonce and fails to properly validate the PayPal capture response status. Attackers can supply a valid _paypal_order_id to trigger payment_complete() without verifying the capture status or amount, causing the store to fulfill goods or services that were never paid for and resulting in direct financial loss to the merchant.