The WannaCry attack caused global disruption in May
A major ransomware attack on Tuesday hit computers at Russia's biggest oil company, the country's banks, Ukraine's international airport as well as global shipping firm AP Moller-Maersk.
Moscow-based cyber security firm Group IB said hackers had exploited code developed by the US National Security Agency (NSA) which was leaked and then used in the WannaCry ransomware attack that caused global disruption in May.
One of the victims of Tuesday's cyber attack, a Ukrainian media company, said its computers were blocked and it had received a demand for $300 worth of the Bitcoin crypto-currency to restore access to its files. "Perhaps you are busy 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.
Other companies also said they had been hit by a presumed cyber attack though it was not clear if their problems were caused by the same virus. Cyber security firms scrambled to understand the scope and impact of the attacks and to identify ways to stop the onslaught.
Researchers with multiple firms identified the ransomware as Petya, malware that makes computers inoperable by encrypting their hard drives and demands ransoms in exchange for a digital key to restore access. "It's like WannaCry all over again," said F-Secure Chief Research Officer Mikko Hypponen. He said it was likely the attack had exploited the NSA hacking tool and he expected the outbreak to be reported in the Americas soon, as workers turned on vulnerable machines, allowing the virus to attack.
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