Which type of malicious software can self-replicate without altering other files or programs?

The type of malicious software that can self-replicate without altering other files or programs is a worm. Unlike a virus, which attaches itself to legitimate programs and files and requires a host to spread, a worm is designed to operate independently. It can replicate itself across networks and can exploit vulnerabilities in operating systems or applications to spread from one device to another. Worms often do not need a host file and can propagate without any user intervention, resulting in widespread replication that can cause significant harm to network resources and bandwidth.

Trojans, on the other hand, disguise themselves as legitimate software but do not replicate themselves at all. Bots may perform automated tasks and can be part of a botnet but typically do not self-replicate independently like worms do. Understanding the characteristics of these different types of malware is essential for developing effective software security practices and responding to potential threats.