The article focuses on the notion of fake information as a tool of psychological influence in the context of hybrid wars. Works of the prominent academicians in the area of manipulation studies constitute the theoretical framework of this research. Empirical research methods such as observation, comparison, generalization and expert evaluation are used. First of all, types and methods of psychological influences used by mass media and social networks with a view to manipulate public opinions are distinguished. Moreover, the impact of emotions on the critical perception of the news is highlighted. The indicators of manipulative influence are defined in order to resist them. Besides, the ways of creating and distributing false information are described. In addition, the development of fakes identification mechanisms is considered a priority for the governmental and other public institutions. This is illustrated by a range of technologies developed to automatically detect fake news. Apart from that, the degrees of the information reliability are explored. Furthermore, structural elements of fake messages, which include the source and the message itself, are discussed. Misinformation of the public, promotion of certain opinions, encouragement of aggressive actions and instalment of doubts are singled out as the main tasks of fake information. Additionally, stages of countering fakes are distinguished. Finally, the specific features of the forensic expertise procedure are determined in order to provide information security in Ukraine. The research demonstrates the importance of an efficient security system, which would identify fake information and limit its propagation.