Morris Worm

What Does Morris Worm Mean?

The Morris worm was a worm designed by Robert Tappan Morris that was released on November 2nd, 1988. It is notorious for being one of the first, if not the first, computer worms distributed on the internet.


Morris, a Cornell grad student, supposedly designed the worm to see how quickly it could spread. A bug in his code infected systems throughout the internet at a faster pace than Morris originally expected, and his worm ended up infecting an estimated 10 percent of the internet. The end result was major damage and widespread outages.

This term is also known as the great worm or the internet worm.

Techopedia Explains Morris Worm

The worm used an exploit in sendmail to transmit a replica of itself. While the worm could only affect DEC VAX machines, part of the worm worked to download its main body onto other systems.

The Morris worm is significant because it served as a wake-up call for the security community. At the time, the internet was more of a close-knit group of academics and hobbyists. Such damage on a large scale, not to mention the widespread media coverage, was a significant factor in the creation of the CERT Coordination Center, which was designed to address internet threats so that the IT community could coordinate a response.

In the end, Morris was convicted under the Computer Fraud and Abuse Act and was sentenced to three years’ probation, 400 hours of community service and a fine of $10,000.


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Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…