Foreign hackers could have broken into North Korean computers and used them to make the country look responsible for hacking Sony, experts have said.
Any attempt to blame North Korea for the attack because hackers used a North Korean IP address “must be treated as suspect”, security firm Cloudmark said. That is one of the reasons that the FBI has given for suspecting the country for the attack, which took down Sony Pictures’ systems for weeks.
Security experts have continued to be dubious of the claim, but FBI officials have continued to blame North Korea.
The country has a very small connection to the internet, run by its national telecom ministry and a Thai firm. As a demonstration of how few connections North Korea has to the internet, Cloudmark said that it has the same amount of IP addresses allocated to it as the entire country.
Cloudmark said that the North Korean addresses it traces tend to send out spam, which is usually the sign of an infected machine. It identified the Wapomi worm, which is transmitted by USB drives and file server shares, as the code that is allowing outside people to control the machine.
While there is no guarantee that the same worm is present on the computers that have carried out the attack, the prevalence of infected computers in the country shows how easy it could have been for Sony’s hackers to give the impression they were based on North Korea.
Cloud mark said that “unless the FBI releases more specific details of their case against North Korea, including email headers and mail server logs, some experts will continue to question if they are in fact correct”.