Fancy Bear is one of the hacker groups we have known about since 2010. Fancy Bear threatened to use Mirai Botnet in the attack. Mirai Botnet was known to target Linux operating systems used in IoT devices. It was mostly known to infect CCTV cameras. Here is a letter from Fancy Bear:

We have talked about a few groups that were infamous for carrying out DoS extortion and some of the techniques used by them. Here are some cases where extortion was carried out using DDoS.