7 Most Catastrophic Computer Viruses of All Time

6. Melissa

Estimated Damage: $1.2 billion

The Melissa virus was a Microsoft Word macro virus which spread as a .doc file that was mass-emailed as a document full of adult website passwords (which at the time were precious). The virus, once activated, caused a globally noticeable slowdown in internet browsing because of the sheer speed of spreading it had.

Most Catastrophic Computer Viruses of All Time - Melissa

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