https://www.scientificamerican.com/article/how-cryptojacking-can-corrupt-the-internet-of-things/

Cyber criminals shut down parts of the Web in October 2016 by attacking the computers that serve as the internet’s switchboard. Their weapon of choice? Poorly secured Web cameras and other internet-connected gadgets that have collectively come to be known as the Internet of Things (IoT). The attack created a minor panic among people trying to visit Sony PlayStation Network, Twitter, GitHub and Spotify’s Web sites, but it had little long-term effect on internet use or the hijacked devices. Less than two years later, however, security experts are sounding the alarm over a new and possibly more nefarious type of IoT attack that “cryptojacks” smart devices, surreptitiously stealing their computing power to help cyber criminals make digital money.

Cryptocurrencies—so called because they use cryptography to secure transactions and mint new virtual coins—are generated when computers loaded with “cryptomining” software perform complex mathematical calculations. The calculations themselves serve no practical purpose, but the faster the computers complete them the more electronic money they make. Cryptojacking (a mashup of the words “cryptocurrency” and “hijacking”) occurs anytime someone uses another person’s internet-connected device without permission to “mine” Ethereum, Monero or some other virtual cash. (Bitcoins are a lot more valuable, but this well-known cryptocurrency is more likely to be created using warehouses of servers rather than someone’s stolen processing power).