The present disclosure provides systems, methods, and computer-readable media for determining an objective measure of breach exposure of Application Programming Interface (API) infrastructure for microservices. In one aspect, a method includes analyzing header information of Application Programming Interface (API) call stacks between microservices; determining, for each API call stack, corresponding security key information based on the header information; determining location information of each of the microservices; and determining a vulnerability score for each of the microservices based on the corresponding security key information and corresponding location information of each of the microservices.