North Korea has hit back at accusations by the US government that it was behind a devastating cyber attack on Sony, and has warned of retaliation as a result.
The US officially accused North Korea on Friday of launching the cyber hack on Sony. The attack saw vast troves of highly confidential company material stolen, and forced the firm to cancel the release of its forthcoming film, The Interview.
However, in a statement released by the North Korean news agency, the government said that the claims by the FBI that the software and IP addresses could be traced to the nation were baseless.
"It is common sense that the method of cyber warfare is almost similar worldwide. Different sorts of hacking programs and codes are used in cyber space," it said, adding that if the allegations continue it will take action against the US.
"Our toughest counteraction will be boldly taken against the White House, the Pentagon and the whole US mainland."
The FBI said on Friday that after analysing the attack it is certain North Korea carried out the hack.
"As a result of our investigation ... the FBI now has enough information to conclude that the North Korean government is responsible for these actions," the agency said.
The FBI explained that it arrived at this conclusion based on several factors. This included analysing the malware used in the attack to cross reference it with other software attacks from North Korea and spotting similar patterns.
The infrastructure used to mount the attack, such as IP addresses, also had overlap with addresses seen in other attacks from the country.
The FBI said there were similarities in the malware to that which hit banks in South Korea in 2013, which was discovered to have come from North Korea. This is most likely the DarkSeoul malware.
The FBI said the nature of the attack posed a severe danger to businesses in the US and the general public.
"North Korea's attack on Sony reaffirms that cyber threats pose one of the gravest national security dangers to the US. Though the FBI has seen a wide variety and increasing number of cyber intrusions, the destructive nature of this attack, coupled with its coercive nature, sets it apart," it said.
"North Korea's actions were intended to inflict significant harm on a US business and suppress the right of American citizens to express themselves. Such acts of intimidation fall outside the bounds of acceptable state behaviour."
The FBI praised Sony for its actions during the attack, noting that its prompt alerts to the FBI made it possible for the agency to identify North Korea as the culprit.
"Sony reported this incident within hours, which is what the FBI hopes all companies will do when facing a cyber attack. Sony's quick reporting facilitated the investigators' ability to do their jobs, and ultimately to identify the source of these attacks," the agency said.
There is now pressure on the US to respond to North Korea after the attack, which is a clear example of the threat hackers can pose to businesses if adequate security controls are not in place.
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