Who is to blame for exposing the NHS to cyber-attacks?

Could the government or intelligence agencies have done more to protect the health service from cybercriminals?

Three days after the WannaCry ransomware outbreak, a string of questions have emerged. Could the US and UK intelligence agencies - the NSA and GCHQ - have done more to prevent the attack? And, in the UK, must the NHS share some of the blame for allowing itself to be so vulnerable?

The chain of events starts with the NSA. It discovered the weakness that made the ransomware so prolific , which was then stolen by a hacking group known as Shadow Brokers, thought to be linked to the Russian government.