A security researcher has demonstrated that jamming WiFi, Bluetooth, and Zigbee networks is not difficult to perform but, most importantly, also not as costly as one might think.
According to Mathy Vanhoef, a PhD student at KU Leuven (Belgium), it can easily be done by using a Wi-Fi $15 dongle bought off Amazon, a Raspberry Pi board, and an amplifier that will broaden the range of the attack to some 120 meters.
The attack would hit all devices within range that operate in the 2.4 and 5 Ghz bands.
With the above mentioned networks being crucial to the functioning of many IoT devices and systems - home security systems, car locks, baby monitors, and so on - it should be obvious that the fact that these attacks can be performed so easily and cheaply may lead to serious consequences.
In fact, it is known that cheap jammers are already being used by crooks around the world:
