According to Brian Krebs, a blogger on security issues, the hackers that broke into Target’s computer network and stole millions of credit and debit card numbers gained access through the network credentials of an HVACR contractor.
Krebs reported that sources involved in the investigation identified Fazio Mechanical Services, a provider of HVAC and refrigeration services located in Sharpsburg, Pa., as the firm whose credentials were stolen in order to gain access to Target’s customer data.