The U.S. law enforcement agency urged the owners of many brands of routers to turn them off and on again and download updates from the manufacturer to protect themselves.
The warning followed a court order Wednesday that allowed the FBI to seize a website that the hackers planned to use to give instructions to the routers. Though that cut off malicious communications, it still left the routers infected, and Friday’s warning was aimed at cleaning up those machines.
Infections were detected in more than 50 countries, though the primary target for further actions was probably Ukraine, the site of many recent infections and a longtime cyberwarfare battleground.