Sony hack 'unprecedented, damaging and unique' cyber security firm says

Since Nov. 24, hackers publicized the salaries and Social Security numbers of thousands of employees of Sony

A cyber security firm investigating the hacking of Sony Pictures Entertainment has called the attack on the studio's technology systems "unprecedented," Michael Lynton, Sony chief executive, told employees Saturday in an email.

"The scope of this attack differs from any we have responded to in the past, as its purpose was to both destroy property and release confidential information to the public," reads a statement which Lynton shared with employees from Kevin Mandia, founder of the cyber security firm Mandiant. "The bottom line is that this was an unparalleled and well planned crime, carried out by an organized group, for which neither SPE nor other companies could have been fully prepared."

Lynton's message to employees, which was obtained by The Times, comes a day after the hacking group Guardians of Peace emailed Sony staffers threatening harm to their families.

Since launching the attack Nov. 24, the group has already publicized troves of sensitive financial information, including the salaries and Social Security numbers of thousands of employees, and uploaded several of the studio's films to the Internet, including its unreleased holiday musical "Annie," which isn't due in theaters until Christmas.

"Over the last week, some of you have asked about the strength of our information security systems and how this attack could have happened," Lynton said in his note to employees. "Mr. Mandia’s note is helpful in understanding the nature of what we are dealing with."

The FBI is investigating the hack, including the possibility that North Korea launched the cyber attack in retaliation for the release of Sony's upcoming film, "The Interview," a comedy that centers on a fictional attempt to assassinate North Korean leader Kim Jong Un.

Twitter: @ThatRebecca

Times staff writer Daniel Miller contributed to this report.

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