A Morrisons’ staff member has been arrested in connection with last week’s data breach, which saw 100,000 employees’ payroll details – including names, addressed and bank details – stolen and posted online, as well as sent to a newspaper.
The supermarket giant said it would continue to work with West Yorkshire Police following the incident and is conducting an urgent review of its internal data systems.
Security experts had already predicted it was an inside job – likely to be an act of revenge or hacktivism – as the perpetrators wanted to make the stolen data public.
Lancope chief technology officer Tim Keanini said: “If they were cyber criminals, it would have been harder to find in the initial stages because it would have been for sale on some darknet and for a price. Also, the data being sent to a newspaper is another sign that the perpetrator wanted it to be a very public event.”
The fact that only employee data appeared to be involved is another sign that the theft is unlikely to be the work of cyber criminals, who would typically go after valuable customer data, said Keanini.
Morrisons has told UK banks about the data loss and is working with them to help colleagues protect their accounts.
The company found out about the theft on Thursday, just after it had reported a £176m loss and warned that profits in the coming year would be less than £375m, about half the level of last year.
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