Method and system for fraud mitigation via account security

A system for customized authentication of a subaccount, comprising:

• an account database of a processing server configured to store an account profile, wherein the account profile includes a structured data set related to a transaction account including at least a plurality of subaccounts, each subaccount including at least (i) an associated account number, (ii) one or more authentication rules defining the types of authentication that are required to authenticate the respective subaccount when used in an attempted transaction and defines properties of the required types of authentication, and (iii) one or more authentication values, wherein the one or more authentication rules defining the types of authentication are configured to differ from one subaccount to another subaccount;
• a receiving device of the processing server configured to receive a transaction message related to a payment transaction, wherein the transaction message (i) is received from a payment network, via payment rails, which are specially configured infrastructure associated with the payment network, (ii) is formatted based on one or more standards, and (iii) includes at least a plurality of data elements including at least a first data element including a transaction account number and one or more additional data elements including authentication data;
• wherein the processing server is configured to:
• execute a query on the account database to identify a specific subaccount in the account profile where the associated account number included in the specific subaccount corresponds to the transaction account number included in the received transaction message;
• authenticate the authentication data based on the one or more authentication rules defining the types of authentication and the one or more authentication values included in the identified specific subaccount;
• and
• using a result of the authentication, modify the transaction message received from the payment network to obtain a modified transaction message, such that the modified transaction message includes the result of the authentication in a data element of the plurality of data elements;
• and
• a transmitting device of the processing server transmitting the modified transaction message to a financial institution associated with the related transaction account,
• wherein the receiving device of the processing server is further configured to receive, from a computing device of a consumer, a subaccount creation request, wherein the subaccount creation request further includes an account identifier, one or more authentication rules, and one or more authentication values,
• wherein the processing server is further configured to:
• identify a subaccount number, and
• execute a query on the account database to insert a new subaccount including
• the identified subaccount number and the one or more authentication rules and one or more authentication values included in the received subaccount creation request, and wherein the account profile further includes the account identifier;
• and
• a transmitting device of the processing server configured to electronically transmit, to the computing device of the consumer, at least the identified subaccount number in response to the received subaccount creation request.