US Patent 12021987 Methods for secure cryptogram generation

A computer-implemented method performed by a user device is provided. The computer-implemented method includes receiving a message including an encrypted credential from a server computer; determining a response shared secret using a private key and a server public key; decrypting the encrypted credential using the response shared secret to determine a credential; obtaining a key derivation parameter from the credential; determining a first cryptogram key using the key derivation parameter; generating a first cryptogram using the first cryptogram key; and sending the first cryptogram to a second computer.