Wary of North Korea's technical skills and the regime's desire to understand US thinking prior to the summit, the US doesn't want to take any chances that North Korean hackers might get into their systems. The intelligence community prioritizes security in its communications and is more regularly working with the private sector to increase its security. The summit has been subject to some uncertainty in recent weeks, following a North Korean threat to cancel in response to routine military exercises between the US and South Korea. The US has long been aware of North Korea's prowess in cyberspace. North Korean hackers are believed to be behind or have played a part in major debilitating cyberattacks including the WannaCry ransomware , which infected hundreds of thousands of computers in 2017, as well as the hack of Sony Pictures Entertainment in 2014.

Source: CNN May 21, 2018 22:16 UTC