What type of malware spreads and executes without requiring user action?

A worm is a type of malware that is designed to spread and execute autonomously without needing any user action. Unlike viruses, which attach themselves to legitimate files and need a user to execute the infected file for propagation, worms are capable of replicating themselves across networks and systems independently. They often exploit vulnerabilities in software or networking protocols to infect other systems, allowing them to proliferate rapidly. This self-propagation ability distinguishes worms from other types of malware, such as Trojans or adware, which typically require some level of user interaction for activation or installation.