Late last year, Target was hit by a major credit-card attack that left millions of accounts vulnerable — and it turns out more than 1,000 other businesses have been affected too, The New York Times reports.
In July, Homeland Security, the Secret Service, and the National Cybersecurity and Communications Integration Center warned companies to check their cash register systems for a malware dubbed “Backoff.”
Some big-name businesses, like Supervalu and UPS, have already stepped forward to say they found the malware, but the Secret Service now estimates that more than 1,000 other businesses have been affected, too.
Criminals can use the Backoff malware to steal unencrypted data from cash register systems they gain access to. The credit card information of millions of Americans is reportedly being sold on the black market, because hundreds of companies don’t realise their systems have been affected by the malware.
On July 31, Homeland Security issued a report telling companies to contact their service providers, antivirus vendors, and cash register system vendors to figure out whether they are vulnerable. The agency re-upped the report on Friday.
“US-CERT is aware of Backoff malware compromising a significant number of major enterprise networks as well as small and medium businesses,” the warning reads.
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