The first sign of trouble was the ATMs. As Britons filled their wallets, the “out of order” signs mushroomed. At the National Cyber Security Centre, experts rapidly spotted the issue: malware on the system that connected ATMs to the banks’ databases.
It copied itself on to every machine it found in the guise of a software update then disabled all further updates. It then spewed out fake messages to the point that genuine communications on the network were swamped.
Technicians had to visit every infected ATM, switch it off and restart with the right software.
In its bunker deep underneath Whitehall, the Cobra committee convened. It was clear Britain was under attack. The obvious answer was Russia. The code showed no sign of origin. Yet…