Europol Suggests Ransomware Cyber-attack Could Grow

It exploited a vulnerability in the Windows operating system believed to have been developed by the National Security Agency, which became public last month.

"We have not yet seen Friday's attack reoccur, there's been no new wave of attacks".

So far there have been no confirmed reports Australian organisations have been hit.

Robert Pritchard, a former cyber security expert at Britain's defence ministry, said security specialists might not be able to keep pace with the hackers.

"There has been no impact on the Australian health system at this stage", he told reporters on Saturday.

Managers at many companies and other organizations have not taken steps to put proper cybersecurity systems in place despite talking about their importance, Gazeley said.

NHS Digital says the attack "was not specifically targeted at the NHS and is affecting organizations from across a range of sectors".

Carmaker Renault was France's first company to be affected by the ransomware while Portugal Telecom and a local authority in Sweden also faced a similar fate.

The European Union's police agency said the attack was at "an unprecedented level and will require a complex global investigation to identify the culprits".

Spain's Telefonica was among the companies hit.

As the fallout from the attack continued, industry officials said law enforcement would find it hard to catch the ringleaders, mostly because such cyberattacks are borderless crimes in which the attackers hide behind complex technologies that mask their identities.

A screenshot of the warning screen ransomware attack, as captured by a computer user in Taiwan, seen Saturday. The team asked users to update antivirus applications and not open suspicious phishing emails.

It remained unclear how many organizations had already lost control of their data to the malicious software - and researchers warned that copycat attacks could follow. However, officials said the day-to-day functioning was not hampered. Several cybersecurity firms said they had identified the malicious software behind the attack, which has apparently hit Russian Federation the hardest. They were forced to reschedule patients, and people were warned to stay away from emergency rooms if possible. It also raised questions about the intentions of the hackers: Did they carry out the attack for mere financial gain or for other unknown reasons?

"Later we found out that the domain was supposed to be unregistered and the malware was counting on this, thus by registering it we inadvertently stopped any subsequent infections", @MalwareTechBlog told CNNTech.

"We're not talking about a government organisation or a hospital or anything like that".

He added: "That's why we're seeing these numbers increasing all the time".

Prime Minister Malcolm Turnbull said the government was ready to deal with cyber attacks.

G7 finance ministers meeting in Italy vowed to unite against cyber crime, as it represented a growing threat to their economies and should be tackled as a priority.

The ransomware encrypted data on the computers, demanding payments of $300 to $600 to restore access.

A hacking group called Shadow Brokers released the malware in April claiming to have discovered the flaw from the NSA, Kaspersky said.

Although a temporary fix earlier slowed the infection rate, the attackers had now released a new version of the ransomware, he said.

"It could have been directed exclusively at Europe but we just don't know".

"The ransomware can spread without anyone opening an email or clicking on a link".

Dr Anne Rainsberry, NHS incident director, said: "We have been working with 47 organisations providing urgent and emergency care who have been infected to varying degrees".

It was not yet known who perpetrated Friday's attacks.

London's Barts Health NHS Trust, the largest trust in the United Kingdom, canceled all outpatient appointments at its five hospitals Saturday. "At this stage, we do not have any evidence that patient data has been accessed".

"Ambulances are being diverted to neighbouring hospitals".

A massive hack crippled computers across the world on Saturday in what was described by experts as a cyberattack on an unprecedented in scale.