LONDON/MADRID—A huge cyberattack brought disruption to Britain’s health system on Friday and infected many Spanish companies with malicious software, and security researchers said a dozen other countries may be affected.
Hospitals and doctors’ surgeries in parts of England were forced to turn away patients and cancel appointments. People in affected areas were being advised to seek medical care only in emergencies.
“We are experiencing a major IT disruption and there are delays at all of our hospitals,” said the Barts Health group, which manages major London hospitals. Routine appointments had been canceled and ambulances were being diverted to neighboring hospitals.
Telecommunications giant Telefonica was among the targets in Spain, though it said the attack was limited to some computers on an internal network and had not affected clients or services.
Authorities in both countries said the attack was conducted using ‘ransomware’—malicious software that infects machines, locks them up by encrypting data and demands a ransom to restore access. They identified the type of malware as ‘Wanna Cry’, also known as ‘Wanna Decryptor’.
A Telefonica spokesman said a window appeared on screens of infected computers that demanded payment with the digital currency bitcoin in order to regain access to files.
