The US Government attributes the massive WannaCry attack Wannacry to North Korea. US Homeland Security Advisor Tom Bossert officially blamed Noth Korea for the attack declaring that the US Government has collected evidence that Link Pyongyang to the massive attack. The news of the attribution was first reported by The Wall Street Journal. North Korea hasnt yet commented the allegation. The US government was expected to follow up with an official statement blaming North Korea for Wanna Cry. The attack caused billions of dollars damages, now the U.S. government has officially blamed the attack.”]
Source: https://securityaffairs.co/wordpress/66926/hacking/wannacry-north-korea.html

