McAfee said that looking at the world’s worst hacks you can see a common pattern – they were not accomplished using the most sophisticated hacking tools.

Writing in IBTImes said that the worst attack was in 2012 attack on Saudi Aramco, one of the world's largest oil companies. Within hours, nearly 35,000 distinct computer systems had their functionality crippled or destroyed, causing a massive disruption to the world's oil supply chain. It was made possible by an employee that was fooled into clicking a bogus link sent in an email.

He said 90 per cent of hacking was social engineering, and it is the human elements in your organization that are going to determine how difficult, or how easy, it will be to hack you.

The user is the weakest link in the chain of computing trust, imperfect by nature. And all of the security software and hardware in the world will not keep a door shut if an authorized user can be convinced to open it, he said.

“Experienced hackers don't concern themselves with firewalls, anti-spyware software, anti-virus software, encryption technology. Instead they want to know whether your management personnel are frequently shuffled; whether your employees are dissatisfied; whether nepotism is tolerated; whether your IT managers have stagnated in their training and self-improvement.”

Muct of this information can be picked up on the dark web and the interernet underground, he added.

“"Are you prepared for a world where grandma or anyone else can quickly obtain, on the wide open web, all of the necessary information for a social engineering hack? Is your organization prepared?” he said.