The paper examines the influence of information attacks on the dynamics of automatic control systems. Comparison of abnormal dynamics of control objects during attacks and device failures is carried out. The similarity of the consequences of information attacks and failures of the control system is analyzed, a method for identifying attacks based on the methods developed for detecting failures is developed. Computer modeling of the influence of information attacks and failures on the control system of a DC motor has been carried out. The simulation results allow making a conclusion about the applicability of the failure detection algorithms for detecting attacks.