Both firms said it was too early to tell whether North Korea was involved in the attacks, based on the evidence that was published on Twitter by Google security researcher Neel Mehta. The attacks, which slowed on Monday, are among the fastest-spreading extortion campaigns on record.
While investigations continue, other cyber security companies are warning that this is just the tip of the iceberg.
Researchers at Bitdefender warned that the attack was going to be one of the most serious threat for the next 12 months.
"Unless, Microsoft decides to do something about it, such as force an update. It has been done before and the scope of the current threat could justify doing it again, in a controlled and coordinates manner, with support from authorities and the security industry," Bitdefender chief security strategist Alexandru Catalin Cosoi, said.
"Although borderline legal, our experience with cyber-crime has proven that legislation is often lagging when it comes to regulation, which is why cooperation between law enforcement and security vendors is needed now more than ever.
"The worst case scenario is for state-actors to use the vulnerability to install backdoors in other governments' public institutions. They could even install the fix/updates themselves, so that nobody else would be able to use the same vulnerability," he said.
Locally, Seccom Global managing director, Michael Demery said that, individual behaviour as much as controls could prevent attacks and the local spread so far showed Australia holding up well.
"As in most instances when an organisation is the victim of an attack, having implemented strong security controls would most likely have minimised the impact, if not stopped the event from occurring in the first place," he said.
"Every person in an organisation has a part to play to ensure that the business remains safe from attacks like the Wanna threats.
"If you do not take Cyber threats seriously, then it is simply a matter of time before you will fall victim to such an attack," he said.
To check whether your computer is protected against the WannaCry ransomware, you can try a free tool, the WannaCry-Checker, which was developed by our sister publication, PC World Germany. Click here to learn more.
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