Russia’s most aggressive ransomware group disappeared. It’s unclear who disabled them. SECTIONS Russia’s most aggressive ransomware group disappeared. It’s unclear who disabled them.By David E. Sanger, New York Times Last Updated: Jul 14, 2021, 07:36 AM IST Share Synopsis While shutting REvil for now would give Putin and Biden a chance to show they were confronting the problem, it could also give the ransomware actors an opportunity to walk away with their winnings. Reuters Just days after President Joe Biden demanded that President Vladimir Putin of Russia shut down ransomware groups attacking American targets, the most aggressive of the groups suddenly went offline early Tuesday.