Sony Picturesに対するサイバー攻撃の真犯人は誰なのか？

下記の記事が出ている。

　The hackers that took down Sony Pictures are still on the attack, researchers say
　Washington Post: February 24, 2016
　https://www.washingtonpost.com/news/the-switch/wp/2016/02/24/the-hackers-that-took-down-sony-pictures-are-still-on-the-attack-researchers-say/

　North Korea linked to Sony hack attack: researchers
　IT News: February 25, 2016
　http://www.itnews.com.au/news/north-korea-linked-to-sony-hack-attack-researchers-415603

　These Are the Cyberweapons Used to Hack Sony
　Motherboard: February 24, 2016
　http://motherboard.vice.com/blog/sony-hack-cyberweapons-report