(FOX News) -- Cyber attacks that hit 74 countries across Europe and Asia Friday, impacting the public health system in Britain, apparently involved a leaked hacking tool from the National Security Agency. The attack used ransomware, which is malware that encrypts data and locks a user from their data until they pay a ransom. The tool, which was leaked by a group known as Shadow Brokers, had been stolen from the N.S.A. as part of a wide swath of tools illegally released in 2016.
Microsoft said that they had rolled out a patch to fix the issue, but certain targets, including the hospitals in Britain, had not yet updated their systems.
The malware was sent via email with a file attached to it. From there, it subsequently spread.
Tom Donnelly, a spokesman for N.H.S. Digital, said the attack was still "ongoing" and that that the organization was "made aware of it this afternoon," according to an interview in The New York Times.
The impact of the attacks caused phone lines to go down, appointments to be canceled and patients to be turned away, but there has been no reported evidence of patient data being breached.
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