The Internet Worm

from a letter by Severo M. Ornstein, in ACM June 89 Vol32 No6

and the appeal notice

On November 2, 1988, Robert Morris, Jr., a graduate student in

Computer Science at Cornell, wrote an experimental, self-replicating,

self-propagating program called a worm and injected it into the

Internet. He chose to release it from MIT, to disguise the fact that

the worm came from Cornell. Morris soon discovered that the program

was replicating and reinfecting machines at a much faster rate than

he had anticipated---there was a bug. Ultimately, many machines at

locations around the country either crashed or became "catatonic."

When Morris realized what was happening, he contacted a friend at

Harvard to discuss a solution. Eventually, they sent an anonymous

message from Harvard over the network, instructing programmers how to

kill the worm and prevent reinfection. However, because the network

route was clogged, this message did not get through until it was too

late. Computers were affected at many sites, including universities,

military sites, and medical research facilities. The estimated cost

of dealing with the worm at each installation ranged from $200 to

more than $53,000. {Derived in part from a letter by Severo M.

Ornstein, in the Communications of the ACM, Vol 32 No 6, June 1989.}

The program took advantage of a hole in the debug mode of the Unix

sendmail program, which runs on a system and waits for other systems

to connect to it and give it email, and a hole in the finger daemon

fingerd, which serves finger requests (Finger). People at the

University of California at Berkeley and MIT had copies of the

program and were actively disassembling it (returning the program

back into its source form) to try to figure out how it worked.

Teams of programmers worked non-stop to come up with at least a

temporary fix, to prevent the continued spread of the worm. After

about twelve hours, the team at Berkeley came up with steps that

would help retard the spread of the virus. Another method was also

discovered at Purdue and widely published. The information didn't

get out as quickly as it could have, however, since so many sites had

completely disconnected themselves from the network.

After a few days, things slowly began to return to normalcy and

everyone wanted to know who had done it all. Morris was later named

in The New York Times as the author (though this hadn't yet been

officially proven, there was a substantial body of evidence pointing

to Morris).

Robert T. Morris was convicted of violating the computer Fraud and

Abuse Act (Title 18), and sentenced to three years of probation, 400

hours of community service, a fine of $10,050, and the costs of his

supervision. His appeal, filed in December, 1990, was rejected the

following March.

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