A computer-readable, non-transitory medium stores therein a verification support program that causes a computer to execute a procedure. The procedure includes first detecting a state change in a circuit and occurring when input data is given to the circuit. The procedure also includes second detecting a state change in the circuit and occurring when the input data partially altered is given to the circuit. The procedure further includes determining whether a difference exists between a series of state changes detected at the first detecting and a series of state changes detected at the second detecting. The procedure also includes outputting a determination result obtained at the determining.