SuperValu, the grocery store operator hit by a cyberattack in June and July, has suffered a second attack on its payment processing system, it said Monday.
The Minnesota-based company said the more recent attack involved different malware installed on the part of its computer network that processes card payments at some of its Shop 'n Save, Shoppers Food & Pharmacy and Cub Foods stores. But the company said it believes that cardholder information is largely safe.
While the second breach is no doubt embarrassing for the company, the severity of the attack was partially mitigated by technology it had deployed since the first breach, it said.
While the malware was installed at numerous stores, it only succeeded in capturing payment card data between Aug. 27 and Sept. 21 from some checkout lanes at four Cub Foods franchise locations in Hastings, Shakopee, Roseville and White Bear Lake, Minnesota.
The data included account numbers, and in some cases the expiration date, the cardholder's name and other data, but even if it was collected, SuperValu said it doesn't believe the captured data was transmitted to a third party.
SuperValu said it has launched a second investigation and that it believes it has eradicated the malware.
The first attack hit the company's payment processing network between June and July and could have resulted in the theft of account numbers, cardholder names, expiration dates and other data from payment cards at some stores in the Shop 'n Save, Shoppers Food & Pharmacy, Farm Fresh and Cub Foods chains.
On Monday, SuperValu said investigations into the first breach are continuing and it hasn't been able to find evidence that any cardholder data was stolen.
The breach is the latest in a growing number to hit payment systems at retail stores.
Martyn Williams covers mobile telecoms, Silicon Valley and general technology breaking news for The IDG News Service. Follow Martyn on Twitter at @martyn_williams. Martyn's e-mail address is email@example.com