From hospitals to telecom companies and even government agencies and business have been targeted by WannaCry, rendering their systems useless.The hackers lock data in such a way that users can not find a workaround and sometimes the pop-ups refuse to close, making it impossible to use the systems. This Malware is expected to be reactivated once the computers are switched on again.
The initial attack, known as "WannaCry", paralyzed computers running factories, banks, government agencies and transport systems in scores of countries, including Russia, Ukraine, Brazil, Spain, India and Japan, among others.
The Federal Government says only three Australian companies have been confirmed as being hit so far, but says more could find they have been compromised when staff turn on their computers this morning.
Grafi said his firm has been contacted by companies that are scrambling to avoid potential pitfalls.
The security blogger is now reportedly working with government's National Cyber Security Centre to prevent a new strain of the malicious software from emerging.
Wainwright said Europol had been concerned about cyber security in the healthcare sector, which deals with a lot of sensitive data, but declined to comment on whether Britain's National Health Service had been adequately funded.
The attack is unique, according to Europol, because it combines ransomware with a worm function, meaning once one machine is infected, the entire internal network is scanned and other vulnerable machines are infected.
Past year an acute-care hospital in Hollywood paid $17000 (R226526) in bitcoin to an extortionist who hijacked its computer systems and forced doctors and staff to revert to pen and paper for record-keeping.
In a blog post, released by Microsoft on Sunday, they called the attack a "wake-up call" and identified "nation-state action and organised criminal action" as "the two most serious forms of cybersecurity threats in the world today".
Meanwhile Europol's chief told the BBC that that the ransomware was created to allow "infection of one computer to quickly spread across the networks", adding: "That's why we're seeing these numbers increasing all the time".
However Home Secretary Amber Rudd said it was important to remember that it was not just the NHS which had been affected.
"Malware that penetrates the perimeter and then spreads inside the network tends to be quite successful", said Johannes Ullrich, director of the Internet Storm Center at the SANS Institute.
Chief Information Security Engineer Roshan Chandraguptha told Lanka Business Online that it is essential to follow precautionary measures to avoid such attack.
Nearly all ransomware takes advantage of a vulnerability in an operating system.
Dozens of local Chinese authorities said they had suspended some of their services due to the attack that has disrupted operations at vehicle factories, hospitals, shops and schools around the world. "We will continue to work with affected (organizations) to confirm this", the agency said.
Government ministers were due to hold an emergency response meeting later on Monday to deal with the crisis.
He said: "The risk and impact of cyber weapons can do the same or more harm than physical weapons".