Citing members of the US intelligence community, the Russian Main Intelligence Directorate (GRU) managed to gain access to some 300 computers, hacked routers and spread malware ahead of and during the Olympic opening ceremony.
Fortunately, the Olympic Games went smoothly, unaffected by this cyber attack. US intelligence members suspect that this attack is a reply because Russian athletes are banned from participating in the Olympics because they are suspected of using doping.
GRU uses North Korean IP addresses to disguise their tracks and make North Korea visible as an offender of this cyber attack. In recent years, North Korea's relations with South Korea and the United States have been strained.
At the start of the event, Olympic organizers confirmed that there had been cyber attacks. However, at that time, they did not mention who the perpetrators of this attack. The attack turned off internet access and WiFi during the Olympic opening ceremony and also disable the official Olympic site.