North Korea is most likely not responsible for the cyberattacks against Sony Pictures Entertainment, which saw thousands of sensitive internal documents released on the Web in a high-profile strike, experts said.
The secretive nation has been fingered in part because the same malware was used against Sony that crippled South Korea in March 2013. Those attacks, dubbed "Dark Seoul," wiped data from banks' computers, disabled ATMs and crippled websites.
It was also theorized that North Korea was angry about a forthcoming movie in the U.S., "The Interview," a comedy in which two show business reporters travel to North Korea to interview leader Kim Jong Un.
But the Sony attacks have been a more public affair, with taunting images displayed on hacked PCs, sensitive company documents posted online and gigabytes of leaked documents sent to journalists.
They are not tactics normally associated with state-sponsored attacks, said Lucas Zaichkowsky, an enterprise defense architect with Resolution1 Security.
"That is almost certainly a hacktivist play," said Zaichkowsky in a phone interview Wednesday.
Zaichkowsky used for work for Mandiant, the computer forensics company now owned by FireEye that has been reportedly contracted by Sony to investigate the attacks. He said the release of gigabytes of data seems more like a move that would come from hacktivists, possibly with connections to disgruntled employees.
A hacking group calling itself the Guardians of Peace (GOP) has claimed responsibility, and a self-proclaimed leader of the group has been sending data to reporters, including IDG News Service.
The group said in an email it was not working on behalf of any state and said its actions against Sony were in part related to the company's restructuring efforts and labor issues.
"Sony and Sony Pictures have made terrible racial discrimination and human rights violation, indiscriminate tyranny and restructuring in recent years," GOP wrote. "It has brought damage to a lot of people, some of whom are among us."
The group said corporate restructuring was the "decisive motive of our action" and called on Sony to "stop this and pay proper monetary compensation to the victims."
"We have another plan to correct the incidents of Michael Brown," the email to reporters added, referring to the fatal shooting of an unarmed man by a police officer in Ferguson, Missouri.
These are hardly the normal concerns of North Korea, and the message doesn't mention "The Interview" at all. It's more consistent with attacks by activist hackers due to its attention-seeking nature, public posting of links to stolen files on Pastebin and reference to social causes.
Jamie Blasco, director of AlienVault Labs, has been analyzing the malware and said the attackers seem to have had knowledge of Sony's internal network.
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