In the first two quarters of 2018, IoT devices grew at an unprecedented rate to hit a total of 7 billion devices. It has been projected that there may be 20.8 billion IoT devices in active use by 2020.
You can find more about this at https://iot-analytics.com/state-of-the-iot-update-q1-q2-2018-number-of-iot-devices-now-7b/.
Going by the numbers from the first two quarters of 2018, the numbers are going to grow quickly. However, there has been a major challenge with IoT devices regarding their security. These devices have been flooded into the market by different manufacturers while lacking the bare minimum security requirements. As a result, many botnets are being formed using these devices.
Botnets are malicious networks of internet-connected devices that are used for performing denial-of-service attacks, or spamming. One of the most powerful botnets today is called...