"Companies are just not doing what they are supposed to do to fix the problem".
Beyond Ukraine and Russian Federation, the wave of cyberattacks also impacted Maersk, a global cargo shipping company and Saint-Gobain, a French company producing construction materials and British-based WPP. Petya reportedly shares some of WannaCry's traits - but while computers that had gotten a security patch were safe from WannaCry, Petya can also infect patched machines.
"We confirm our company's computer network was compromised today as part of a global hack".
Cert NZ advised businesses and individuals to regularly update and back up their IT systems.
For the moment, Ukraine has been the country most affected by the attack, which targeted the Kiev metro, the state-run Ukrenergo electricity company, the Ukrtelecom telephone company and several cell phone operators, among many other firms.
Mr Moran said companies that had made the required amendments to their IT systems following May's incident should be protected from the latest attack.
The NSA did not respond to a request for comment. The exploit was leaked - along with a number of other hacking tools - by Shadow Brokers in April 2017.
Several private security experts have said they believe Shadow Brokers is tied to the Russian government, and that the North Korean government was behind WannaCry.
In Ukraine the virus struck the country's government administration.
In another of the affected countries, Danish transport and logistics company Maersk also said that "multiple sites and business units" had been shut down after the cyber attack.
The attacks on Russian and Ukrainian companies involved a type of ransomware that locks users out of the computer and demands purchase of a key to reinstate access, said cybersecurity company Group IB. "Perhaps you are looking for a way to recover your files, but don't waste your time. Nobody can recover your files without our decryption service", the message said, according to a screenshot posted by Ukraine's Channel 24. Ukraine was the first to report these attacks, as the National Bank of Ukraine released a statement. One consumer lender, Home Credit, had to suspend client operations.
And French construction materials company St Gobain has said that it had fallen victim.
It also recalled a ransomware outbreak last month which hit more than 150 countries and a total of more than 200,000 victims with the WannaCry ransomware.
For advice from the Department of Homeland Security on how to avoid ransomware attacks, go here.