On Monday, Hackers were demanding $70 million in bitcoin in exchange for data stolen during an attack on a US IT company that has shuttered hundreds of Swedish supermarkets.
Researchers believe more than 1,000 companies could have been affected by the attack on Miami-based firm Kaseya, which provides IT services to some 40,000 businesses around the world.
The FBI warned on Sunday that the scale of the “ransomware” attack — a form of digital hostage-taking where hackers encrypt victims’ data and then demand money for restored access — is so large that it may be “unable to respond to each victim individually”.
Sweden’s Coop supermarket chain was among the most high-profile victims.
Most of their 800 stores were still closed three days after the hack paralysed its cash registers, spokesman Kevin Bell said.
Coop, like many of the companies affected, is not a direct customer of Kaseya’s, but its IT subcontractor Visma Esscom was hit by the attack.
The few hundred Coop stores that had reopened were relying on alternative payment solutions, such as customers paying using their smartphones, Bell said.
Cybersecurity firm ESET said it had identified victims of the hack in at least 17 countries, from South Africa to Britain to Mexico. New Zealand’s education ministry said at least two schools there had been affected.