Target

Rescator, a hacker only known by this name stole the login credentials from the HVAC vendor which was working with Target’IT network. He used those credentials to help him gain access to POS terminals and harvest of Target and swiped nearly every card over a several months period. The attacker pilfered 11GB of extremely sensitive data. This resulted in banks spending $350 million reissuing cards. Public findings showed the debacle cost Target more than $252 million in losses. 110 million shoppers lost their credit card data.