The FBI on Friday formally linked North Korea’s government to the devastating hack into Sony Picture Entertainment’s computer system.
In a statement, the FBI cited technical analysis of the malware as well as similarities to prior attacks associated with 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,” the FBI stated.
The cyber-attack rendered thousands of Sony’s computers inoperable, forced the company to take its entire computer network offline, and significantly disrupted the company’s business operations, law enforcement officials say.
“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,” the FBI stated. “For example, there were similarities in specific lines of code, encryption algorithms, data deletion methods, and compromised networks.”
The FBI further noted that the Sony attack has similarities to a cyber attack in March of last year against South Korean banks and media outlets, which was carried out by North Korea.
A group calling itself the “Guardians of Peace” claimed responsibility for the attack and subsequently issued threats against Sony, its employees, and theaters that distribute its movies. In response, the company canceled the opening of “The Interview,” a putative comedy about a U.S. plot to assassinate North Korea’s leader Kim Jong Un.
“North Korea’s actions were intended to inflict significant harm on a U.S. business and suppress the right of American citizens to express themselves,” the FBI stated. “Such acts of intimidation fall outside the bounds of acceptable state behavior.”
Homeland Security Secretary Jeh Johnson, in a statement that did not specifically mention North Korea, said Friday that “the cyber attack against Sony Pictures Entertainment was not just an attack against a company and its employees. It was also an attack on our freedom of expression and way of life.”