What mechanism do stealth viruses use to go undetected?

Stealth viruses employ a particularly cunning tactic to evade detection by disguising themselves as legitimate files. This ability to camouflage is crucial in ensuring that they can integrate into a system unnoticed. When a stealth virus infects a file, it often modifies the file's structure or behavior in a way that protects its presence. By mimicking legitimate processes or files, it can circumvent standard security scans which may not flag these disguised entities as threats.

The other mechanisms mentioned, such as replicating excessively or remaining inactive, do not primarily describe the stealth characteristics. Disabling antivirus software is also a tactic seen in various forms of malware, but it does not encompass the essence of stealth viruses. Instead, the core functionality of stealth viruses lies in their ability to hide within legitimate software, making the disguise as legitimate files the defining tactic.