This thesis presents a comprehensive vulnerability assessment of Internet of Things (IoT) devices, structured into both theoretical and practical analyses. In the initial phase, an extensive theoretical study is conducted focusing on the intrinsic architecture of IoT devices, firmware analysis and the exploration of known vulnerabilities. This foundational work establishes the necessary background to understand the security challenges inherent in these systems. Subsequently, the thesis shifts to a practical examination of the communication protocols employed by IoT devices such as Tapo cameras and smart plugs, Shelly, and Sonoff switches, focusing on how these devices interconnect within the same network and communicate with their respective servers.