Hundreds of French supermarkets experienced refrigeration disruptions after hackers reportedly manipulated control systems overnight, destroying fresh and frozen food.
Intermarché, Netto, Coopérative U, and Leclerc stores were among those affected, with potential nationwide losses reaching several million euros, according to BFMTV. The incident targeted refrigeration systems supplied by the Danish manufacturer Danfoss.
Les Mousquetaires confirmed that 300 Intermarché and Netto stores were affected, double the initial estimate of 150 outlets. Coopérative U separately reported disruptions at fewer than 100 stores. The number of affected Leclerc locations remains unspecified, making an accurate nationwide total impossible.
Hackers Target French Supermarkets
According to industry professionals cited by BFMTV, attackers targeted older versions of Danfoss control software, specifically those preceding version 4.
They allegedly abused the refrigeration equipment’s automatic defrost function, turning a routine maintenance operation into extended heating.
Defrost cycles are intended to remove accumulated frost and typically run for about two hours within 24 hours. During the attack, hackers allegedly forced continuous defrosting and set a temperature of 50°C.
This figure reflects the temperature setting the attackers chose, not the confirmed temperature reached in every affected refrigerator. BFMTV imagery showed an ice cream aisle at 26°C, and an industry source described a “wave of heat” escaping when staff opened the equipment.
This mechanism demonstrates operational technology manipulation: unauthorized changes to control parameters led to physical consequences rather than merely disrupting business applications.
However, the report does not identify a specific exploited vulnerability, controller model, authentication bypass, or initial access method. References to older software versions do not indicate a specific vulnerability or confirm that newer versions are unaffected.
Some attacks began around midnight, letting refrigeration equipment run for several hours before employees arrived. Stores affected later in the night salvaged some of their fresh stock.
In Haguenau, an Intermarché supermarket reportedly lost its entire frozen inventory, with damages estimated at €50,000. A Leclerc store in Wasselonne discarded both frozen and fresh products, estimating losses of €220,000. Another Leclerc location in Haguenau was also affected but had not quantified its losses.
These local estimates illustrate the financial impact, although the nationwide multimillion-euro figure remains an industry estimate rather than an audited total.
Les Mousquetaires said affected stores took precautions to remove products from disrupted equipment quickly. An internal communication dated October 12 warned of potential losses of frozen products and offered priority handling for exceptional replenishment orders.
Coopérative U established crisis units alongside refrigeration specialists to support affected stores. Danfoss and refrigeration installation and maintenance provider Axima scheduled a meeting for the following Monday morning.
Coopérative U’s leadership described the attacks against equipment vital for preserving food as “extremely serious, unprecedented, and unacceptable.”
The reported consequences extend beyond unavailable checkout or ordering systems: manipulation of refrigeration controls directly threatened stock preservation, forcing retailers to discard products while coordinating equipment recovery and replacement deliveries.
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