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Melissa virus

(also W97M.Melissa, virus:W32/Melissa, Melissa)

Melissa virus definition

The Melissa virus is a macro virus (malicious software that spreads using macro-enabled files) that was released by David L. Smith on March 26, 1999. The Melissa virus can quickly overwhelm Microsoft Outlook and Microsoft Exchange servers because it propagates through mass emails.

The Melissa virus gained notoriety as the fastest-spreading virus of its time. Its rampant spread alerted the public to the dangers posed by emerging cyberthreats and the need for effective cybersecurity measures.

See also: antivirus, computer virus, email virus, macro virus, email bomb

How the Melissa virus works

The virus infected devices through compromised Microsoft Word documents. Once the device was infected, Melissa would exploit Microsoft Outlook to automatically send infected Word documents to the first 50 email addresses in the victim’s contact list, typically with a message designed to intrigue recipients.

Stopping the Melissa virus

  • Update your software with the latest security patches. The Melissa virus relies on vulnerabilities in older Microsoft Word and Outlook products that have since been patched out.
  • Disable macros in Microsoft Office applications to prevent the execution of malicious commands embedded within infected documents.
  • Use reputable antivirus software to detect, block, and remove malware like the Melissa virus.
  • Enable email filtering to quarantine potentially malicious emails.
  • Avoid opening email attachments unless you are expecting them and can verify their authenticity with the sender.
  • Practice good cyber hygiene and learn to avoid the most common online threats.

Watch it explained: Melissa virus