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Internet worm

(also computer worm)

Internet worm definition

An internet worm is a type of malware that self-replicates and distributes copies of itself across a network. By spreading by itself, the worm infects computers and systems without showing any signs to users. Internet worms usually utilize bugs in computer software to attack the systems. Compared to other types of malware, like trojans, internet worms are more dangerous because they spread on their own, and they can easily bypass many forms of network security, such as firewalls.

Internet worm real-life examples

  • Morris worm. It was the first internet worm to have a massive impact. It crashed over 6,000 computers.
  • WannaCry/WannaCryptor. It encrypted the Windows users’ files and asked for payment to recover them.
  • ILOVEYOU/Love Bug/Love Letter worm. This worm appeared as a love letter through email attachments, damaging over 10 million computers.
  • Nimda worm. Nimda offered malicious downloads through emails and LANs and changed existing websites.
  • Code Red worm. This worm caused a DDoS attack on the US White House.
  • MSBlast/Blaster. This worm forced computers to shut down.
  • Sobig worm. It spreads through email by using frequent subject lines.
  • Jerusalem/BlackBox worm. The worm overtook computer resources and infected .exe files until they became too big to handle.

Preventing internet worms

  • Regularly update your software and OS.
  • Utilize reputable antivirus software.
  • Don’t open email attachments from unknown users.
  • Avoid unmoderated file-sharing sites.
  • Use a firewall that helps block suspicious traffic.