Your vendors card reader taken over by a rogue credit card.  I’ve seen this on tv but never thought it was for real.  This is why i constantly tell folks to update EVERYTHING they can…even card readers now are computers running..Linux.  However there was a vulnerability in the app for the reader which allowed any firmware update to be installed… without checking for authenticity.  Simply swiping a card told the reader to go download a new reader software that not only read the cards but also sent the data to the thieves at this large chain.

 

Thieves Hack Barnes & Noble Point-of-Sale Terminals at 63 Stores | Threat Level | Wired.com.