Virus (Computer)

A computer virus is a piece of malicious code that inserts itself into a legitimate program, document or system area and copies itself when that host is run, spreading to other files and machines. Strictly, a virus needs a host and some action, such as opening an infected file, to spread, which separates it from a worm, which spreads across networks on its own. In everyday speech "virus" is often used for any malware. Viruses can delete data, steal information or open the way for other attacks, such as ransomware or a keylogger. Crypto users face malware that swaps copied wallet addresses or steals wallet files and seed phrases. Defences include anti-malware software, updates, caution with downloads and keeping large holdings on separate hardware. Also see cybersecurity risk.