Just days after President Biden demanded that President Vladimir V. Putin of Russia shut down ransomware groups attacking American targets, the most aggressive of the groups suddenly went off-line early Tuesday.
The mystery is who made it happen.
The group, called REvil, short for “Ransomware evil,” has been identified by U.S. intelligence agencies as responsible for the attack on one of America’s largest beef producers, JBS. Two weeks after Mr. Biden and Mr. Putin met in Geneva last month, REvil took credit for a hack that affected thousands of businesses around the world over the July 4 holiday. Continue reading.