How the Target hackers did it

Hackers responsible for carrying out a massive theft of credit and debit card information from the retailer Target likely used sophisticated variations of tools that have been circulating in the computer underground for a long time, according to report prepared by cyber security firm iSight Partners and the U.S. Department of Homeland Security.

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The report explained that malware aimed at "point of sale" or POS machines, is sold in black markets and is generally well-known to law enforcement. The popularity of the software, iSight said, may lead to a demand for more custom-made attack tools. In July of 2013 in one marketplace for freelance hackers — think of it as a Craigslist for criminals — as many as 20 percent of the ads were for the creation of POS malware.

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By Arik Hesseldahl,

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