Morris worm

The Morris worm was one of the first internet distributed computer worms; it is considered the first worm virus and was certainly the first to gain significant mainstream media attention. It was written by a student at Cornell University, Robert Tappan Morris, and launched on November 2, 1988 from MIT.

The Morris worm was not written to cause damage but to spread; bugs in the code, however, caused it to be more damaging - a computer could be infected multiple times and each additional process would slow the machine down to the point it would be unusable. The Morris worm worked by exploiting known vulnerabilities in Unix sendmail, fingerd, rsh/rexec and weak passwords. It could only infect DEC VAX and Sun 3 systems.

Around 6,000 major Unix machines were infected by the Morris worm. The GAO put the cost of the damage at $10m - $100m. Robert Morris was tried and convicted of violating the 1986 Computer Fraud and Abuse Act (Title 18). After appeals he was sentenced to three years probation, 400 hours of community service, and a fine of $10,000.

CERT (the Computer Emergency Response Team) was created as a response to the Morris Worm.

The jargon file refers to this as the "Great Worm":

Great Worm n.

The 1988 Internet worm perpetrated by RTM. This is a play on Tolkien (compare elvish, elder days). In the fantasy history of his Middle Earth books, there were dragons powerful enough to lay waste to entire regions; two of these (Scatha and Glaurung) were known as "the Great Worms". This usage expresses the connotation that the RTM crack was a sort of devastating watershed event in hacker history; certainly it did more to make non-hackers nervous about the Internet than anything before or since.