E-mail Worms

In short: E-mail worms spread by sending themselves to contacts from the victim’s address book.

In more detail: They usually come as an attachment with a tempting subject. If someone opens the attachment, the worm reads the address book and sends itself on, often with its own SMTP function.

In Depth

Well-known examples

Melissa (1999), ILOVEYOU (2000), Mydoom (2004). Mydoom at times caused a large share of the world’s mail traffic.

Protection

Do not open attachments of unknown origin, mail servers with virus filters, show file extensions (otherwise “bild.jpg.exe” seems to be “bild.jpg”).

See also: Worms, E-mail Attachments, Spam E-mail