IoT devices are almost the perfect target for cyber thieves for the following reasons: They have their own IP address and make it possible to communicate with other connected network devices and systems. One insecure device at the right moment is all it takes to create an attack vector in IT and OT networks. A malicious attacker that has successfully gained entry into an internal routing and switching infrastructure can monitor, modify, and even deny traffic between key hosts inside a network. Even an innocent thermometer sitting in a fish tank can be hooked into a hackers net and serve as a stepping stone to a critical database.”]
Source: https://informationsecuritybuzz.com/articles/how-does-iot-expand-hackers/