Which kind of malware requires user intervention (typically unintentional) to spread from computer to computer and frequently causes important files to disappear while showing a taunting message?

Numerous viruses will alert that you're infected as soon as they enter your system. They might gain access to your computer, show annoying messages on your screen, or destroy your disk. You'll be able to tell that you're a victim when this happens. Other viruses can slow down your system, delete files from your computer, or take up all of your disk space. These days, email is used to spread several viruses. Any email you send to another user is automatically attached with a file by the infected system. The recipient opens this file, believing it to be something you sent them legitimately. The virus enters the target system when they open the file. A group of computers used to launch an attack without the knowledge of the computer's authorized user is known as a botnet. The computer is referred to as a "zombie," and a third-party attacker controls it. When you install seemingly innocent-looking files, a Trojan—malicious software that hides in an entertaining game or screensaver you just downloaded—is installed. Malware known as a rootkit can take full control of a system after logging in as the administrator. Rootkits are challenging to get rid of because they are good at concealing their presence.