An FBI investigation has found that North Korea was responsible for the cyber attack on Sony Pictures
The FBI has now officially blamed North Korea for the Sony Pictures hack. In a statement it said it was "deeply concerned about the destructive nature of this attack on a private sector entity and the ordinary citizens who worked there," adding that cyber attacks like this "pose one of the gravest national security dangers to the United States."
Sony was praised for its quick reporting of the hack and was described as "a great partner" in the investigation.
The FBI gave three reasons for coming to the conclusion that North Korea was responsible. They include:
Technical analysis of the data deletion malware used in this attack revealed links to other malware that the FBI knows North Korean actors previously developed. For example, there were similarities in specific lines of code, encryption algorithms, data deletion methods, and compromised networks.
The FBI also observed significant overlap between the infrastructure used in this attack and other malicious cyber activity the U.S. government has previously linked directly to North Korea. For example, the FBI discovered that several Internet protocol (IP) addresses associated with known North Korean infrastructure communicated with IP addresses that were hardcoded into the data deletion malware used in this attack.
Separately, the tools used in the SPE attack have similarities to a cyber attack in March of last year against South Korean banks and media outlets, which was carried out by North Korea.
It added that the Sony attacks "have similarities" to a cyber attack in March 2013 on South Korean banks and media outlets, which was carried out by North Korea.
Although not mentioned in the report, a Chinese link is thought to have come from hackers using servers based in the country.
A day earlier, it was thought that the hack was an inside job, possibly performed by a disgruntled former Sony employee, and that the North Korea link was one created by the media, but doubt has now been cast over this theory.