The undetectable and unprovable hardware Trojan horse

We have developed an approach for automatic embedding of customizable hardware Trojan horses (HTHs) into an arbitrary finite state machine. The HTH can be used to facilitate a variety of security attacks and does not require any additional gates, because it is morphed into the specified design. Even after the HTH induces provable damage, one is not capable of proving that any malicious circuitry is embedded into the design. The main ramification of the developed HTH is that hardware and system techniques should move from HTH detection toward synthesis for trusted systems.