A California computer security firm says hackers are using large networks of computers to spread viruses, send spam and steal sensitive information.
Symantec warns of a dramatic rise in the number of computers taken over by "bot" networks, which allow scam artists to automatically start widespread Internet attacks from their own computers, the Washington Times reported Monday.
Symantec said the number of machines infected this way rose from about 2,000 per day at the beginning of the year to an average of 30,000 per day by June.
"We're seeing a land grab of vulnerable systems," said Brian Dunphy, Symantec's director of global analysis. "(Criminals) are becoming a little bit more organized. Rather than just sending a worm out to run around the Internet, they're becoming more controlled about how they get control of systems."
Internet experts blamed an attack from a large "bot" network for a broad outage in June of several major Web sites, including those of Akamai, Apple, Microsoft and Yahoo.
"Bot" networks are becoming common because they allow criminals to take control of more systems and collect more personal data from those machines, Symantec said. The rights to use those compromised machines are often sold to fellow criminals for hundreds, if not thousands, of dollars.
© Copyright 2004 by United Press International
