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SAN FRANCISCO — Investigators say they believe they have identified the entry point through which hackers got into Target’s systems, zeroing in on the remote access granted through the retailer’s computerized heating and cooling software, according to two people briefed on the inquiry.
The latest revelation highlights the reality that a large company is actually a sprawling network of interconnected vendors, and that weak security at any one vendor can lead to a breach that costs hundreds of millions of dollars.
Target, Neiman Marcus and the Michaels chain of arts and crafts stores are among the major retailers whose systems have been hacked with what investigators suspect is similar malware that invades the computerized register system and snatches consumer data, according to people with knowledge of the investigations. But it has not been disclosed whether other companies were possibly invaded through outside vendors with remotely controlled access.