Avast recently did analysis on a malware they named 'Torii'. Torii works on a wide range of devices and has a modular design that makes it easily able to data fetch and command execution. Telnet is the only vector currently used, but researchers worry that the authors of the malware have other vectors as well. Torii is an example of how IoT malware is evolving and getting more sophisticated. The relevant URL from Avast has more information about Torii and also depicts domains and IP's to monitor for a Torii infection.