The Sony attackers are still unknown (@SaTechie/Twitter)

In a “flash” warning issued to businesses on Monday evening, the FBI provided advice on how to respond to the malware and to contact the FBI if they detected similar malware.

The warning said that the malware functions by overriding all data on the hard drives of computers and prevents them from booting up. The report said, “The overwriting of the data files will make it extremely difficult and costly, if not impossible, to recover data using standard forensic methods.”

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The FBI continues to investigate the Sony attack with help from the Department of Homeland Security.

Read more about the cyber security breach at Reuters.

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