Disclosed herein are representative embodiments of methods, apparatus, and systems for maintaining the security of certain sensitive user information during computer network transactions between the user and multiple third-party hosts. Some example embodiments disclosed herein comprise a computer-implemented method, comprising, at a server separate from a merchant server and separate from a payment processor server: receiving data indicative of a transaction initiated by a customer from the merchant server; generating a unique identification value for the transaction; transmitting, to a customer's computing device, identifying information for a Uniform Resource Locator (URL) that is unique to the transaction; receiving a request to view a web page at the URL that is unique to the transaction; and generating data for a hosted-pay web page unique to the transaction, the hosted-pay web page including an embedded portion that facilitates payment directly with a payment processor server and not with a merchant server.