Cyberattack Disables Refrigeration at Hundreds of French Supermarkets

Hundreds of French supermarkets had their refrigeration systems knocked out overnight between October 11 and 12, 2026, after hackers remotely triggered continuous defrost cycles in cooling units, according to retailers and French officials. The intrusion targeted equipment made by the Danish manufacturer Danfoss and left fresh and frozen food sections unusable at stores run by several of France's largest grocery groups.

What happened

Refrigerators and freezers at affected stores were remotely reset to around 50°C instead of cooling temperatures, according to France's public broadcaster franceinfo, which cited a source close to the matter. The forced defrost ran for hours overnight, melting frost-control systems and spoiling meat, dairy and frozen goods in butcher counters and cold aisles.

Coopérative U chief executive Dominique Schelcher described the incident as 'unprecedented,' saying in a statement reported by IT-Connect and Euronews: 'Targeting equipment essential to the preservation of fresh products and to the food supply of the French people is extremely serious and is unprecedented.'

Which chains and how many stores

Exact store counts differ between the retailers' own disclosures and reporting as of October 12, reflecting how fast-moving and still-unconfirmed parts of the incident are.

Euronews reported that E.Leclerc's and Monoprix's involvement had not been confirmed by the companies themselves at the time of its report, while franceinfo gave higher Intermarché figures and a specific Monoprix percentage, illustrating that the full scale was still being established as the story developed.

How the attack worked

According to franceinfo, Danfoss identified the vulnerable equipment as two controller models, the AK-SM800 and AK-SC355, which it said 'have reached their end of life and no longer benefit from software updates or security patches.'

IT-Connect reported that the attackers exploited older versions of Danfoss's refrigeration-control software, predating version 4, and linked the incident to vulnerabilities that security researchers had already disclosed publicly at the DEF CON conference in August 2026. Danfoss had already released a patched firmware version, R4.3.1, addressing the flaws following that disclosure, IT-Connect reported.

• CVE-2025-41450: an authentication bypass using a date-based hidden password
• CVE-2025-41451: a command-injection flaw enabling remote code execution
• CVE-2025-41452: an Nginx configuration-injection issue causing denial of service

Official response and investigation

According to Euronews, the Paris prosecutor's office confirmed it had opened an investigation into what it called a large-scale cyberattack affecting cold-storage equipment at several major French food-distribution chains, with the stated aim of identifying those responsible and establishing links between the intrusion and the reported food losses.

franceinfo reported that France's Prime Minister was personally following the situation and that ANSSI, the national cybersecurity agency, was involved and had identified the vulnerability in the Danish-made software. No group or individual had claimed responsibility for the attack as of October 12, and none of the sources reviewed named a suspect.

Financial and food-safety impact

Affected stores were required to document spoiled stock with a bailiff's report before discarding perishable goods, franceinfo reported. A source cited by franceinfo put potential losses at 'several million euros' nationwide, though no retailer had published a precise figure by the time the outlets were reviewed. Euronews reported that Intermarché warned some losses might not be covered by existing insurance policies.

None of the three sources reviewed for this article reported any confirmed impact on online ordering, home-delivery scheduling or shelf pricing systems at the French chains; franceinfo noted specifically that no information had been provided on those systems, and the reporting focused on physical refrigeration equipment.

What remains unknown

• No attacker or group has been publicly identified or has claimed responsibility.
• The exact total number of stores affected varies between sources and had not been finalized as of October 12.
• Precise, company-confirmed financial loss figures had not been published.
• Whether online retail systems, beyond refrigeration hardware, were affected in France had not been confirmed by any source reviewed.