Hackers hijacked refrigeration systems at French supermarkets and raised fridge temperatures until food spoiled and fires broke out, Reuters reports.

The attackers gained control of connected cooling equipment and pushed temperatures up instead of down. The manipulation spoiled stock and, in at least some stores, generated enough heat to start fires.

The incident targets the operational technology layer that retailers increasingly run on connected networks: refrigeration controllers, energy management systems and remote monitoring dashboards. Unlike ransomware that encrypts data, this attack caused physical damage — burned equipment, ruined inventory and store closures while systems were inspected and reset.

For European grocery and hospitality operators, the case exposes a specific gap. Commercial refrigeration and HVAC systems often sit on the same networks as tills and back-office software, yet they receive fewer security updates and less monitoring than IT assets.

The attack method also complicates detection. Raising a setpoint by a few degrees produces no obvious alarm. Losses surface gradually as spoilage, until heat build-up triggers fire suppression or staff notice smoke.

What should operators do now?

• Audit which refrigeration and building-management systems are reachable from external networks.
• Segregate operational technology from payment and corporate IT segments.
• Set alerting on any setpoint change, not just on system outages.
• Include physical-damage scenarios, not only data loss, in incident response plans.

No operator names, attack dates or loss figures have been disclosed so far. French authorities have not yet published attribution findings.