Teams of Russian and Ukrainian hackers stole more than 1 million credit card numbers from 40 American e-businesses in recent months, according to the Federal Bureau of Investigation. Then the hackers threatened to plaster the purloined customer data all over the Internet unless the targeted companies bought their "security" services. The FBI calls the scheme, which unfolded over several months, one of the biggest hacker attacks in the history of the Web, and said that it believed stolen data has been sold to organized crime groups.

The FBI refused to name the companies that fell victim to the hackers, although law enforcement officials implied that the targets were all online merchants and Internet banks. The hackers took advantage of well known and easy-to-fix vulnerabilities in Windows NT operating systems, as well as some Unix-based systems.

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