Cyberattack forces French supermarket fridges to defrost, hundreds of stores hit

How the attack unfolded

Hackers took control remotely of the systems that manage commercial refrigeration during the night of Sunday 11 to Monday 12 October, forcing continuous defrost cycles instead of cooling. Instead of lowering temperatures, the units warmed the cabinets, and by the morning of Monday 12 October warm air escaped from the display cases, according to SudOuest.fr, with readings sometimes above 26 °C. Citing BFMTV, ČT24 reported that the temperatures set remotely reached as high as 50 degrees. The attack reportedly exploited equipment from the Danish manufacturer Danfoss, whose supervision boxes and software regulate store temperatures. The prime minister's office said the national cybersecurity agency had identified a vulnerability in software supplied by a Danish company and had contacted its publisher.

Which chains were affected

AFP estimated that 150 to 200 Intermarché stores and almost 100 Coopérative U stores were hit. The Mousquetaires group, which runs Intermarché, counted 300 affected Intermarché and Netto stores, while Coopérative U said fewer than 100 of its outlets were affected. Franceinfo reported that E.Leclerc confirmed several of its stores had been hit, whereas SudOuest.fr reported losses of up to 220,000 euros at one Leclerc site that the group had not confirmed. Carrefour Market, Monoprix and Metro were named in media reports but did not confirm being affected. Messages on social networks pointed to Intermarché stores in Parempuyre, Port-Sainte-Foy and Gradignan in the Gironde, while two supermarkets in Haguenau in Alsace recorded losses of goods worth 270,000 euros.

Losses and insurance

Intermarché told AFP that affected shops would have to throw away all fresh and frozen products. The chain blamed the attack for food waste and financial losses but did not give an estimate of the damage. It warned that insurance policies may not cover incidents of this kind. The Mousquetaires group believes refrigeration systems have never before been subjected to such an attack. French media put the damage in the range of millions of euros across the country.

Investigation and government response

The Paris prosecutor's office opened an investigation on its own initiative and entrusted it to the Office anticybercriminalité (OFAC). The aim is to identify all victims and formally link the hack to the food losses and the fires. Prosecutors said fires had also been set. The Ministry of Trade said it was in contact with distributors and had no further information at that stage. Prime Minister Sébastien Lecornu asked ANSSI on Monday 12 October to take over the matter, and his office said he is following the file personally. ANSSI is in contact with European counterparts because other countries may be affected, and it is trying to identify other French companies concerned so it can warn and advise them before the problem spreads.

Reactions

Dominique Schelcher, chief executive of Coopérative U, confirmed the attack on X and condemned it in these words:

Targeting equipment essential for keeping fresh products and supplying food to the French is extremely serious and unprecedented.

Schelcher wrote that the company's teams were fully mobilised to fix the problems and that an investigation would be needed to fully clarify the attack. The Intermarché store in Haguenau said on Facebook that, like many other shops, it had fallen victim to a hacking attack on its cooling system. It added that it had to throw away all frozen products.