The invention provides a system, a secure device and a method for authenticating dynamically a host device with a secure device without modifying hardware or basic functional software of the host device. An authentication engine implemented in the secure device allows detecting non-authorized host devices or illegal secure devices environment. The secure device is locally connected to the host device comprising at least one processor configured for handling a plurality of hardware or software parameters defining the functioning behavior of the host device. A memory associated to the processor stores a plurality of reference hardware and software parameters. The secure device monitors the behavior of the host device both in terms of hardware and software. After comparison with the reference parameters, the host device is considered as authentic or authorized only when the values of counters associated to the hardware and software parameters are within an acceptable.