The basic scope of the study of this thesis work is attack detection in the direct data-driven control. Attacks which are potentially may violate the work of sensors and actuators, accordingly an outcome of the controller. The main concept of the direct data-driven control is to design a controller, which will correspond output of the system to a given reference model, having in disposition only measured input and output data, in other words without knowing the exact structure of the plant itself. Taking into consideration the errors that may interfere with the signal during the measurement of the input and output data, the feasible controller parameter set is defined.