Virus-like program that spreads automatically to other computers by sending itself out by email or by any other means. A program that propagates itself by attacking other machines and copying itself to the affected machine.
Worms have self-replicating code that travels from machine to machine by various means. A worms first objective is merely propagation. Worms can be destructive depending on what payload they have been given. Worms may replace files, but do not insert themselves into files.
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W32.Netlip.Worm is a worm that attaches itself to email messages each time that you send email to anyone from an infected computer. The virus may trick a user into running it since it has Windows folder icon association - on a default system where extensions of known file types are hidden, the file will appear exactly like a Windows folder.
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