Interfax and Fontanka in Russia have both been hit by a cyber attack, as have Odessa Airport and the Kiev Metro in Ukraine.
"Based on our investigation, this is a targeted attack against corporate networks, using methods similar to those used in the ExPetr attack," Kaspersky Lab has said. "However, we cannot confirm it is related to ExPetr."
The cyber criminals behind Bad Rabbit are locking computers down and demanding 0.05 Bitcoin (£220) from victims, in exchange for the restoration of their devices.
However, security experts always advise people against paying the ransom. This is because it encourages more attacks, and there's no guarantee the attackers will actually honour their word and remove the malware from your device.
According to the Bad Rabbit ransom screen, the fee will rise in the near future.
Ukraine’s cyber police chief has told Reuters that the country was “barely affected”.
In May, the “WannaCry” ransomware attack forced hospitals, factories and businesses around the world to shut down because they could not access critical computer systems.
NotPetya took down a number of Ukrainian government agencies and businesses in June, before spreading rapidly through corporate networks of multinationals with operations or suppliers in eastern Europe.
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