13. A device for protecting vulnerable services from null-byte insertion, comprising: memory; and processing circuitry coupled to the memory, the memory storing program code which, when executed by the processing circuitry, causes the processing circuitry to: generate, in the memory, an output finite-state machine, using a set of directed graphs stored in the memory, wherein each one of the directed graphs in the set corresponds to a singly encoded null-byte that is encoded according to a corresponding one of a set of character encoding methods, and wherein the output finite-state machine models computation for detecting at least one multiply encoded null-byte, the multiply encoded null-byte encoded according to at least one of the character encoding methods contained in the set of character encoding methods; load the output finite-state machine into an attack detection and prevention system in the program code stored in the memory; and detect, in response to the output finite-state machine loaded in the attack detection and prevention system and an input text, an instance of the multiply encoded null-byte within the input text.
13. A device for protecting vulnerable services from null-byte insertion, comprising: memory; and processing circuitry coupled to the memory, the memory storing program code which, when executed by the processing circuitry, causes the processing circuitry to: generate, in the memory, an output finite-state machine, using a set of directed graphs stored in the memory, wherein each one of the directed graphs in the set corresponds to a singly encoded null-byte that is encoded according to a corresponding one of a set of character encoding methods, and wherein the output finite-state machine models computation for detecting at least one multiply encoded null-byte, the multiply encoded null-byte encoded according to at least one of the character encoding methods contained in the set of character encoding methods; load the output finite-state machine into an attack detection and prevention system in the program code stored in the memory; and detect, in response to the output finite-state machine loaded in the attack detection and prevention system and an input text, an instance of the multiply encoded null-byte within the input text. 14. The device of claim 13 , wherein each one of the directed graphs in the set of directed graphs comprises an input finite-state machine that models computation for detecting a singly encoded null-byte that is encoded according to the corresponding one of the encoding methods in the set of encoding methods.