WannaCry FAQ: How does WannaCry spread? WannaCry has multiple ways of spreading. Its primary method is to use the Backdoor.Double.Pulsar backdoor exploit tool released last March by the hacker group known as Shadow Brokers, and managed to infect thousands of Microsoft Windows computers in only a few weeks. Because DoublePulsar runs in kernel mode, it grants hackers a high level of control over the compromised computer system.
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