Craft Commerce is an ecommerce platform for Craft CMS. In versions 4.0.0 through 4.10.2 and 5.0.0 through 5.5.4, the PaymentsController::actionPay discloses some order data to unauthenticated users when an order number is provided and the email check fails during an anonymous payment. The JSON error response includes the serialized order object (order), which contains some sensitive fields such as customer email, shipping address, and billing address. The frontend payment flow's actionPay() retrieves orders by number before authorization is fully enforcedLoad order by number. This issue has been fixed in versions 4.11.0 and 5.6.0.