Both Bloomberg and Reuters claim to have talked to individuals who are part of the investigation that have outlined their suspicions.
They believe that the malware is ripe with Korean hacking code and bears distinct similarities to hacks on South Korean banks in March last year.
The attack on Sony Pictures computers caused widespread disruption and resulted in the theft of company information, personal data and even some forthcoming movies, which appeared on unternet sites earlier this week.
North Korea is furious about a film called The Interview which describes an attempt by two journos to assassinate the country’s autocrat, Kim Jong Un (pictured, with two military folk).
North Korea claims the release of the film later this month should be regarded as an act of war.