Although the investigation into the incident is not yet over, from the evidence found by agents so far, the FBI has concluded that the North Korean government is responsible for the attack on Sony, which has now taken on global proportions.
In late November, a group of hackers calling themselves “Guardians of Peace,” or GOP, hacked into the computers of Sony Pictures Entertainment (SPE). Large amounts of confidential information, both personal and commercial, were stolen.
The company responded by hiring Mandiant, a FireEye company, and requesting assistance from the FBI, hours after the attack was reported.
"As a result of our investigation, and close cooperation with other government agencies and organizations, the FBI now has sufficient information to conclude that the government of North Korea is responsible for these acts," an official statement from the FBI made last week said.
It appears that the FBI has found a lot of evidence to support this theory, but is only revealing part of it in order to protect sensitive sources and the methods they used to find the evidence. It says that it found lines of code, encryption algorithms, data deletion methods that have been used in other attacks known to have been carried out by North Korean actors.
It is also noted that some of the infrastructure used in the SPE attack has been used in other attacks that the US government has directly linked to North Korea. Evidence of this was various IP addresses found encrypted within the attack malware.
