The information is believed to have been lifted from those card swiping devices at store registers between November 27 and December 15. Hackers somehow got access to the data stored on the magnetic strip of cards used in stores only, not online.
Officials say check your statements very carefully. If you see suspicious charges, report them right away.
The good news is in most cases, consumers aren't on the hook for fraudulent charges but don't expect to get a refund overnight. That process could take several weeks.