I doubt the CIA is only involved in one technical attack and not others.
Disclaimer: I know and have worked with the people on Operation Blockbuster.
I don't know if the CIA did or would want to do this specific attack.
But, I could grasp at straws to fit the Sony attack in line with the narrative of what I would call "1950s American Imperialism".
In my view, the Americans took covert or overt actions for many decades now to undermine economically competitive countries. We've bombed Germany, Italy, Japan, Serbia, Korea, China, Vietnam... we've invaded Iraq... we've taken actions against many Latin American governments and Iran...
Over the years, the powers at be have been pretty good at framing other nations for attacks or dangers, in order to drum up public support to attack them. Gulf of Tonkin, WMDs, USS Vincennes...
So, in short, if you had definitive proof that Russian and NK hacking were in fact orchestrated by the CIA...
... then the economic imperialism narrative would hold as pretty plausible motives!
The most blatant endgame here for the US is "NK hacked us. They have nukes! It's time to invade!". And then NK becomes a new market for the West to take over for cheap as they did in Communist Yugoslavia and so on
But "They have nukes!" would be reasonable enough reason to invade. Why not work with that narrative as opposed to "They're hacking us!"?
Some might say the US has a moral obligation to pursue regime change in N Korea, but US foreign policy has focused on isolating as opposed to invasion
Perhaps it is convenient fear-mongering and deepening of arguments. America seems to be pretty good at spreading multi-faceted arguments about why you shouldn't even _think_ about the legitimacy of a multi-polar world.
I guess my point is, the American government and official state media seem pretty content to have these multi-bullet playbooks against nations that are quite deeply fulfill the criteria of "non-western", "non-democratic", "non-capitalist", but still quite serious "economic and militaristic threats"
Stuxnet was (in a sense) a much more interesting topic than this leak. It showed that the retaliation is pursued not only by isolation and sanctioning, but with (subtle & undercover) direct attacks too.