Pros don't seem to think North Korea is to blame.
From a good Wired post
New reports, however, indicate that intelligence officials who are not permitted to speak on the record have concluded that the North Koreans are behind the hack. But they have provided no evidence to support this and without knowing even what agency the officials belong to, it’s difficult to know what to make of the claim. And we should point out that intelligence agencies and government officials have jumped to hasty conclusions or misled the public in the past because it was politically expedient.
Nation-state attacks aren’t generally as noisy, or announce themselves with an image of a blazing skeleton posted to infected computers, as occurred in the Sony hack. Nor do they use a catchy nom-de-hack like Guardians of Peace to identify themselves. Nation-state attackers also generally don’t chastise their victims for having poor security, as purported members of GOP have done in media interviews. Nor do such attacks involve posts of stolen data to Pastebin—the unofficial cloud repository of hackers—where sensitive company files belonging to Sony have been leaked. These are all hallmarks of hacktivists—groups like Anonymous and LulzSec, who thrive on targeting large corporations for ideological reasons or just the lulz, or by hackers sympathetic to a political cause.
Despite all of this, media outlets won’t let the North Korea narrative go and don’t seem to want to consider other options. If there’s anything years of Law and Order reruns should tell us, it’s that focusing on a single suspect can lead to exclusionary bias where clues that contradict the favored theory get ignored.
Possibly an inside job or maybe with help from a disgruntled employee?
Cybersecurity expert Hemanshu Nigam also finds it hard to believe that North Korea is the perpetrator. Instead, he theorizes an employee or ex-employee with administrative access privileges is a more likely suspect. For the studio — which has laid off hundreds of employees over the past year in an effort to contain costs — the possibility of a disgruntled employee wreaking havoc is very real.
Don't have the technical capabilities.
"It could be. In my personal opinion, it's not," Monsegur said. "Look at the bandwidth going into North Korea. I mean, the pipelines, the pipes going in, handling data, they only have one major ISP across their entire nation. That kind of information flowing at one time would have shut down North Korean Internet completely."
Monsegur is confident they don't have the infrastructure to carry out this kind of attack.
An opportunity to argue for more elite/corporate control of the interent?
Of course Fox News is sure North Korea is behind it, probably with help from all of our other enemies, Iran, Russia and China. What the hell is the administration going to do about it? Why won't they act? Obama is weak? Benghazi!
Ain't propaganda wonderful...