The article discusses the security issues of the three-tier IoT architecture, consisting of the physical, network, and application layers. The emphasis is placed on the importance of protecting IoT systems from cyber attacks, which can have serious financial consequences and also affect human security. The existing possibilities of using current machine learning algorithms in order to detect and prevent cyber threats are considered. The study focuses on the two lower levels of the IoT architecture, as the application layer requires separate analysis due to a variety of attacks, including social engineering. The work is aimed at in-depth understanding of IoT vulnerabilities and at offering effective methods of overcoming them, using modern technologies.