Recent victims have included large corporations such as retailer London Drugs, as well as the City of Hamilton, Ont., and the government of Newfoundland and Labrador.
Retailer London Drugs says cybercriminals who stole files from its corporate head office last month have released some of the data after it refused to pay a ransom.
A government source later said the incidents were related to a directive to all provincial employees early last week that they should immediately change their passwords.
Confused shoppers milled around the front of a London Drugs store in downtown Vancouver on Monday, some wondering aloud why they couldn't access the store to get prescriptions or buy hair dye.