By Brian Livingston
I like to think back on the good old days, when the worst thing Windows might do to us was crash.
Now we have to defend ourselves against invisible programs that silently take over our PCs, record our keystrokes to capture our banking passwords, use our bandwidth to send out junk e-mails that can’t be traced back to the senders, and then bury us in the spam we receive in turn from all the other PC users whose machines have been similarly hacked.
This week, Symantec, the antivirus and security company, released its sixth semiannual Internet Security Threat Report. It says the firm found a vast increase in the number of “bot networks” that are under the control of hackers. Each network consists of thousands of machines that have been infected with Trojan horses and are now controlled by criminals.
During the first six months of 2004, Symantec detected a rapid growth of bot networks from fewer then 2,000 to 30,000. The number of PCs in each network is said to average around 2,000. Multiply the number of networks by the average population of controlled machines and it works out to 60 million “zombie” PCs — that we know about.
Symantec found one bot network consisting of 400,000 zombies, according to an article by John Markoff in the New York Times. Each network can be used to broadcast spam, launch devastating denial-of-service attacks against Web sites the hackers don’t like, and more.