Major French supermarket chains were hit by a cyberattack described as unprecedented, forcing refrigeration systems to defrost and spoil food.
At least 300 Intermarche or Netto shops, over 100 Cooperative U outlets, and several E. Leclerc stores were affected.
Attack targeted Danfoss legacy fridge controllers with outdated firmware, which Danfoss had long warned needed updating.
Paris prosecutors opened an investigation after reports the attack sparked fires, while authorities alerted other countries and suppliers.