Botnet
Adversaries may compromise numerous third-party systems to form a botnet that can be used during targeting. A botnet is a network of compromised systems that can be instructed to perform coordinated tasks. Instead of purchasing/renting a botnet from a booter/stresser service, adversaries may build their own botnet by compromising numerous third-party systems.
Adversaries may also conduct a takeover of an existing botnet, such as redirecting bots to adversary-controlled C2 servers. With a botnet at their disposal, adversaries may perform follow-on activity such as large-scale Phishing or Distributed Denial of Service (DDoS).