Secure processing of central bank digital currency (CBDC) card payments

A system for conducting a transaction using a central bank digital currency (CBDC), the system comprising:

• at least one hardware processor;
• and
• at least one non-transitory memory storing instructions, which, when executed by the at least one hardware processor, cause the system to:
• receive, from a payment terminal, a payment message, wherein the payment message contains a signature transmitted to the payment terminal by a payment card,
• wherein the payment message contains a terminal signature of the payment terminal,
• wherein the payment message contains an acquirer identity,
• wherein the payment message comprises a request to conduct the transaction, and
• wherein the payment card is associated with a payer account that holds one or more tokens of a CBDC, the one or more tokens to be transferred in the transaction from the payer account to a payee account;
• access a payee public key associated with an acquirer associated with the acquirer identity;
• generate a signature data structure containing a representation of the signature,
• wherein the signature data structure is generated as a unique state on a ledger of a distributed ledger environment, and
• wherein the unique data state is consumed as part of the transaction;
• and
• generate a transaction message that includes the signature data structure,
• wherein the transaction is validated based on the signature data structure and verifying the terminal signature using the payee public key.

A non-transitory, computer-readable storage medium comprising instructions recorded thereon that, when executed by at least one processor of a system, cause the system to:

• receive, from a payment terminal, a payment message,
• wherein the payment message that contains a signature transmitted to the payment terminal by a payment card,
• wherein the payment message contains a terminal signature of the payment terminal,
• wherein the payment message contains an acquirer identity,
• wherein the payment message comprises a request to conduct a transaction, and
• wherein the payment card is associated with a payer account that holds one or more tokens of a central bank digital currency (CBDC), the one or more tokens to be transferred as part of the transaction from the payer account to a payee account;
• access a payee public key associated with an acquirer associated with the acquirer identity;
• generate a signature data structure containing a representation of the signature,
• wherein the signature data structure is generated as a unique state on a ledger of a distributed ledger environment, and
• wherein the unique state is consumed as part of the transaction;
• and
• generate a transaction message that includes the signature data structure,
• wherein the transaction is validated based on the signature data structure and verifying the terminal signature using the payee public key.