U.S. officials publicly attributed the global WannaCry ransomware attack to North Korea after an investigation supported by allied governments and private-sector analysis. The malware rapidly encrypted hundreds of thousands of computers across more than 150 countries, affecting hospitals, schools, businesses, governments, and home users; in the UK healthcare sector, the disruption created risks beyond financial loss. The briefing says Microsoft traced the attack to cyber affiliates of the North Korean government, while Microsoft, Facebook, and other technology companies disrupted accounts, exploits, and infected activity linked to North Korean hackers. DHS issued technical alerts to help defenders identify and remove North Korean malware from networks, using WannaCry as evidence that public-private coordination and timely patching are critical against destructive state-linked activity.