What is Dridex, and how can I stay safe?

The malware's authors have stolen 20m from UK bank accounts over the past year, but after arrests, the flow should stop

• Cyber-attack warning after millions stolen from UK bank accounts

Dridex is the name of a strain of malware designed to eavesdrop on victim's computers in order to steal personal information such as usernames and passwords, with the ultimate aim of breaking into bank accounts and siphoning off cash.