A signal malware sends out to the command and control server, indicating that it has infected a device and asking for further instructions. It can also be used to send out collected data (for example, login credentials or credit card details). The attacker configures how often the malware checks in and how before infecting their target. Malware may lay dormant for days or weeks before some predetermined conditions are met (for example, the victim visits their bank’s webpage) and the payload is executed.