An analysis by Japan’s GMO Internet Group found that a North Korea-linked hacking group was likely behind the cyberattack on the company last month, sources close to the matter said, citing characteristics of the malware used and other traces left by the perpetrators. The company appears to have already reported the matter to the government and will now focus on determining the full circumstances. Kyodo News, working with security experts, also found that five IP addresses used to access a...