MANILA, Philippines – The US Federal Bureau of Investigation (FBI) warned US businesses Monday, December 1, of malicious software (malware) that may have been used by hackers to attack Sony Pictures Entertainment in the United States.

Reuters reports the FBI released a confidential 5-page alert to businesses late Monday, giving some technical details of the malware used in the attack.

The warning noted the malware overrides the data on the hard drives of computers, including the master boot record. By doing this, the drive is prevented from starting, and it makes the data recovery using standard forensic methods “extremely difficult and costly, if not impossible” to accomplish.

Cybersecurity experts said the malware described in the alert seems to describe the one used against Sony Pictures Entertainment. The attack against Sony Pictures brought the company’s corporate email down afor a week and affected other systems. Some of Sony Pictures’ unreleased films were also made available online following the attack.

Sony Pictures Entertainment has since hired FireEye Inc’s Mandiant forensics unit to assist in the restoration of its systems.

Technology website Re/Code wrote on November 28 that Sony Pictures Entertainment was exploring the possibility that hackers working on North Korea’s behalf were responsible for the attack.

The Re/Code report notes the attack’s timing coincides with the upcoming release of “The Interview,” a comedic film that shows a CIA plot to assassinate North Korea’s leader, Kim Jong-Un.

The BBC reports that North Korea has refused to deny involvement in the cyberattack on Sony Pictures Entertainment.

“Wait and see,” replied a spokesman for the North Korean government when asked about whether the country was involved in the cyberattack on Sony Pictures. – Rappler.com

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