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Page 707
propagating even if the system administrator there started up his own version of the
worm to fool the real worm. The use of one in seven created far too many worms,
and was the reason all the infected machines ground to a halt: they were infested
with worms. If Morris had left this out and just exited whenever another worm
was sighted (or made it one in 50) the worm would probably have gone undetected.
Morris was caught when one of his friends spoke with the
New York Times
ence reporter, John Markoff, and tried to convince Markoff that the incident was an
accident, the worm was harmless, and the author was sorry. The friend inadver-
tently let slip that the perpetrator’s login was
. Converting
into the owner’s
name was easy—all that Markoff had to do was to run
The next day the
story was the lead on page one, even upstaging the presidential election three days
Morris was tried and convicted in federal court.
He was sentenced to a fine of
$10,000, 3 years probation, and 400 hours of community service. His legal costs
probably exceeded $150,000.
This sentence generated a great deal of controversy.
Many in the computer community felt that he was a bright graduate student whose
harmless prank had gotten out of control. Nothing in the worm suggested that Mor-
ris was trying to steal or damage anything. Others felt he was a serious criminal
and should have gone to jail.
Morris later got his Ph.D. from Harvard and is now a
professor at M.I.T.
One permanent effect of this incident was the establishment of
Computer Emergency Response Team
), which provides a central place to
report break-in attempts, and a group of experts to analyze security problems and
design fixes. While this action was certainly a step forward, it also has its down-
side. CERT collects information about system flaws that can be attacked and how
to fix them.
Of necessity, it circulates this information widely to thousands of sys-
tem administrators on the Internet. Unfortunately, the bad guys (possibly posing as
system administrators) may also be able to get bug reports and exploit the loop-
holes in the hours (or even days) before they are closed.
A variety of other worms have been released since the Morris worm. They op-
erate along the same lines as the Morris worm, only exploiting different bugs in
other software. They tend to spread much faster than viruses because they move on
their own.
9.9.4 Spyware
An increasingly common kind of malware is
, Roughly speaking, spy-
ware is software that is surrepitiously loaded onto a PC without the owner’s know-
ledge and runs in the background doing things behind the owner’s back. Defining
it, though, is surprisingly tricky. For example, Windows Update automatically
downloads security patches to Windows without the owners being aware of it. Sim-
ilarly, many antivirus programs automatically update themselves silently in the

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