The most common security threats in IoT include unauthorized access, data breaches, and device hijacking. Weak authentication, outdated firmware, and lack of encryption make IoT devices vulnerable to cyberattacks. Attackers can exploit these gaps to control devices remotely or steal sensitive data. Botnet attacks, such as Mirai, have shown how compromised IoT devices can be used for large-scale disruptions. Securing networks, regular software updates, and strong password protocols are essential to mitigate these risks. Understanding these threats is crucial for building safe and reliable systems. Start exploring this domain with an IoT certification course to build secure solutions.