WASHINGTON – Investigations circling Target's massive data breach are pointing to a sophisticated operation that took advantage of vulnerabilities at one of the company's contractors to access the retail giant's customer information.
A Secret Service official on Wednesday called the criminals "highly technical and sophisticated," while the chairman of a House subcommittee investigating the breach pointed to a "process failure" such as an accessible password as the likely security gap they were able to exploit.
"I didn't hear a smoking gun," Rep. Lee Terry, R-Neb., said Wednesday after questioning Target Chief Financial Officer John Mulligan at a hearing. But "it looked like it was a process failure."
Details of how the attackers were able to access payment card and personal information from as many as 110 million Target customers late last year have been slow to emerge.
But as Mulligan appeared for a second day on Capitol Hill, the blogger who first revealed the breach quoted sources saying the attackers gained access to the network credentials of a Pennsylvania provider of refrigeration and ventilation systems.
KrebsOnSecurity reported that attackers first broke into the retailer's network Nov. 15 using network credentials stolen from Fazio Mechanical Services of Sharpsburg, Pa.
"Fazio President Ross Fazio confirmed that the U.S. Secret Service visited his company's offices in connection with the Target investigation," the blog reported.
Target declined to comment on whether Fazio was involved.