A massive cyberattack using leaked NSA exploits has hit 99 countries, and it's still spreading

A huge cyberattack is spreading across the globe, and a software exploit developed by the National Security Agency seems to be to blame.

The ransomware, software that encrypts the victim’s data and demands a ransom to unlock it, has spread to at least 99 countries, from England to Japan, as of Friday.

Among the organisations affected are Britain’s National Health Service, the Spanish telecommunications firm Telefónica, and the logistics firm FedEx.

The cyberattack has caused chaos across the United Kingdom. Hospitals have been closed and operations cancelled on short notice, and medical staffers have resorted to pen and paper to do work.

Both NHS and Telefónica confirmed the attacks. They said they had been hit by versions of the so-called WannaCry ransomware that demands at least $US300.

The reason for the ransomware’s virulent spread appears to be its use of an exploit of Windows software developed by the NSA, an American intelligence agency. The exploit was leaked online months ago and patched by Microsoft, but those affected seem not to have updated their software to install the fix.

The security firm Avast told CNN it had detected the ransomware in at least 99 countries.

CCN-CERT, the Spanish computer-emergency response team, published an advisory about the ransomware and pointed to Microsoft’s patch.

“The ransomware, a version of WannaCry, infects the machine by encrypting all its files and using a remote command execution vulnerability through SMB is distributed to other Windows machines on the same network,” the organisation said.

Some 85% of Telefónica’s computers have been affected, according to El Mundo. Portugal Telecom was also hit by a cyberattack on Friday, but its services weren’t affected, a spokeswoman told Reuters. She didn’t say whether it was a WannaCry attack.

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