Aug. 23--The U.S. Secret Service is warning that more than 1,000 U.S. businesses have been hit by the same type of cyberattack that has already affected Target and Cub-owner Supervalu, the New York Times reported Friday.
The wave of attacks, coming through cash register systems, is far more widespread than earlier acknowledged. Data from millions of credit and debit cards are being stolen "without companies knowing about it, according to a new Department of Homeland Security advisory," the Times reported.
While both Target and Supervalu have disclosed that hackers have broken into their payment systems, most companies have not revealed it, in part because they do not yet know.
Millions of stolen card numbers are being resold through online "card shops," to criminals worldwide.
In an advisory issued Friday, Homeland Security warned of malware -- dubbed "Backoff" -- that is "compromising a significant number of major enterprise networks as well as small and medium businesses."
The Times reports that seven companies that sell and manage in-store cash register systems told federal officials that each had "multiple clients affected" by the cyberattack.
Copyright 2014 - Pioneer Press, St. Paul, Minn.