Export to PDF/Word are services that generate PDF/Word files based on the data provided by the customer (HTML, CSS). To perform the conversion, they require the data sent from the editor or a database, but the services themselves are fully stateless.
The sensitive data (HTML, CSS, comments) is used only during the processing and then removed from the servers after the document is created and returned to the user.
All data transmission between CKEditor / Customer's application and CKEditor Cloud Services infrastructure is encrypted with TLS 1.2+.