Target's Massive Data Breach Originated With A Singe Phishing Email

The massive data breach at Target that affected up to 110 million shoppers has been traced back to a single phishing email, security blogger Brian Krebs is reporting.

The malware-laced email was sent to an employee of Fazio Mechanical, a Pennsylvania heating and air conditioning company that was doing business with Target, Krebs wrote, citing sources close to the investigation.

After gaining access to the employee's computer, the hackers could then enter Target's computer system, according to the report. Fazio confirmed last week that it was "the victim of a sophisticated cyber attack operation."