The WannaCry ransomware worm infected systems at organizations and critical infrastructure across at least 74 countries leveraging NSA exploits. Experts discovered a Kill Switch for the threat. The massive ransomware attack was first observed targeting UK hospitals and Spanish banks, big companies like Telefnica, Vodafone, FedEx has some of their systems infected with the threat that also hit rail stations and universities. Most of the infections were observed in Russia, Ukraine, and Taiwan. The malware implements network warm capabilities that allow it to rapidly spread. Infection of a single computer can end up compromising the entire corporate network.”]
Source: https://securityaffairs.co/wordpress/59072/cyber-crime/wannacry-ransomware-kill-switch.html