Hackers forced temperatures in refrigeration units at hundreds of French supermarkets up to 50 degrees Celsius overnight, causing fires and widespread food losses in what officials described as an unprecedented cyberattack.
The Paris prosecutor's office confirmed Monday that a "large-scale" attack targeted "connected refrigerators in several major food retailers across France," resulting in "food losses and fires."
Between 150 and 200 Intermarché stores, including outlets of its Netto brand, were affected, according to Les Mousquetaires, the group that owns the chain. Refrigeration units in those stores reached 50 degrees Celsius and remained at that temperature for approximately six hours. The company discarded all fresh and frozen products to avoid sanitary risks.
Coopérative U reported that more than 100 of its supermarkets were targeted. The chain's chief executive, Dominique Schelcher, described the attack as "extremely serious and unprecedented," adding that it was "unacceptable" to target equipment essential to food preservation and the food supply of the French people.
Carrefour said 80 of its supermarkets were hit. Monoprix reported that 5 percent of its stores were affected. E. Leclerc stores were also targeted, though the group did not immediately confirm the extent of the damage to AFP.
Hackers gained control of software regulating the refrigeration units, remotely activating defrost cycles. The affected equipment was manufactured by Danish company Danfoss. A Danfoss representative noted that most compromised units were running outdated firmware.
Preliminary damage estimates reached millions of euros. Two affected stores in eastern France reported combined stock losses of 270,000 euros.
Prime Minister Sébastien Lecornu instructed France's National Cybersecurity Agency ANSSI to investigate the incident. Officials said France was coordinating with European counterparts because other countries may also be affected. A senior cyber threat intelligence analyst at Sekoia Threat Detection and Research said Spain, Portugal, Poland, Germany and Belgium had also been affected.
Authorities were also investigating whether other French companies faced similar risks. The identities of the hackers remained unknown as of Monday.