Hacking groups linked to North Korea will continue to devastate the UK with major cyberattacks over the next year, former GCHQ director Robert Hannigan has warned.
Referencing WannaCry, a malware outbreak which has been linked to the rogue state, the ex-spy chief said there will be "more collateral damage and more unintended consequences."
"The technical sophistication of the threats is going to get worse, without question," Hannigan said during a recent FT cybersecurity summit in the heart of London. "We'll see more ransomware, we'll see a greater scale of attacks," he added.
WannaCry, a rapidly-spreading form of ransomware, emerged back in May and eventually affected hundreds of thousands of computers in 150 countries.
In the UK, the National Health Service (NHS) was hit in the cyber-assault. It was not specifically targeted, but instead was a victim of what Hannigan branded "collateral damage."
"WannaCry was really a reasonably sophisticated tool, used rather ineptly," he commented.
"They will learn from that. People always do. They will get better at using those tools, and there are far more sophisticated tools out there, and they will start to use them."
He added: "If you look at the NHS, nobody would seriously believe that the North Koreans wanted to attack the NHS, and not least because they were never going to pay a ransom."
According to data released by the National Audit Office (NAO), nearly 20,000 appointments were disrupted by the incident.
An independent audit found "basic IT procedures" could have halted the hack.
Hannigan voiced concern about the overlap of state and crime in cyberspace.
He noted: "The critical thing is that there are players out there now behaving badly enough not really to care.
"Either because they don't have a stake in the international system, or they have a stake but actually, that's a threshold of damage that they can live with in order to deliver whatever effect they want to deliver. And they would expect the rest of the world just to live with that.
"I think we will see more of that - more collateral damage and more unintended consequences."
While attribution will never be 100% concrete, a clandestine unit known as "Lazarus Group" was linked to the WannaCry outbreak by similarities in hacking tools spotted in other incidents.
UK security minister, Ben Wallace, told the BBC in October the government "quite strongly" believed North Korea was responsible for the cyberattack on the healthcare system.
"I obviously can't go into the detail of intelligence, but it is widely believed in the community and across a number of countries that North Korea had taken this role," he said.
Hannigan quit as GCHQ chief in January this year, citing personal reasons. In September, it emerged he had been appointed as cybersecurity advisor to insurance firm Hiscox UK and Ireland.
His stance on hacking has been echoed by those still working for the government.
In late October, National Cyber Security Centre (NCSC) chief Ciaran Martin warned that he expected a "significant scale attack" on the UK is likely to take place in the coming years.