US Patent 11336454 Systems and methods for cryptographic authentication of contactless cards

Example embodiments of systems and methods for data transmission between a contactless card and a client application are provided. A card key may be generated using a master key and identification number. A first and second session key may be generated using the card key and portions of the. A cryptographic result including the counter may be generated using one or more cryptographic algorithms and the card key. A cryptogram may be generated using the first session key and encrypted using the second session key. The application may be transmit one or more messages to the first applet of the contactless card. The first applet may be configured to establish one or more communication paths to the second applet based on receipt of the one or more messages from the client device. The second applet may be deactivated by the first applet via the one or more communication paths.