French Supermarket Freezers Hacked to Reach 120°F

Paris prosecutors have opened a dedicated cybercrime investigation into the incident, which the Paris prosecutor's office described as a large-scale cyber-attack affecting refrigerators at several major French food retail chains. The intrusion centered on software from Danish engineering company Danfoss that lets supermarkets monitor and manage refrigeration equipment remotely. Retailers including Coopérative U, Intermarché and its Netto brand, Carrefour, Monoprix and E.Leclerc reported problems.

More than 100 Coopérative U supermarkets were targeted, while about 180 Intermarché and Netto stores were affected, according to the source. Another 100 shops were disconnected from the internet as a precaution. Based on figures from individual chains, roughly 400 of France's approximately 15,000 supermarkets may have been affected, though the full scale remains unclear. Carrefour said 80 of its 6,000 stores had compromised refrigeration systems, and Monoprix said around 5% of its more than 400 locations were affected.

Supermarket freezers normally run a short overnight defrost cycle, but attackers reportedly manipulated the controls to keep units heating for hours instead. Intermarché told Reuters that temperatures in affected units reached 50°C (120°F) and stayed there for six hours overnight into Monday. Danfoss did not confirm those maximum temperatures. The company said the affected equipment was older models whose security software could not be updated to address a known vulnerability, and it added that it had long advised businesses to keep supported systems up to date.

When employees arrived Monday morning, some reportedly encountered waves of hot air from refrigeration units, and small fires were reported at certain stores. BFMTV released an image of a freezer in an ice cream aisle showing 79.7°F (26.5°C), far above safe frozen-storage temperatures. Dominique Schelcher, chief executive of Coopérative U, called the incident an 'extremely serious and unprecedented' attack. Mousquetaires Group, parent of Intermarché and Netto, told the BBC that some fresh and frozen display units remained out of service Monday afternoon; the group said stores had removed products from those units and were working to restock shelves as soon as possible.

BFMTV reported that two supermarkets in the Alsace region suffered combined losses of €270,000, about $302,000, with the total nationwide cost potentially reaching millions of euros. European Food Commissioner Christophe Hansen condemned the attack in a post on X, saying food security needs more attention at all levels and that the weaponization of food has become a reality. The investigation is expected to examine how attackers gained access to refrigeration controls and whether the incident exposed wider weaknesses in supermarket infrastructure.