Attackers Heat French Supermarket Fridges Up to 50°C by Hijacking Danfoss Controllers

On the night of October 11, attackers remotely hijacked refrigeration controllers made by Danish company Danfoss at hundreds of French supermarkets. The attackers raised temperatures in fridges and freezers to as high as 50°C, causing widespread food spoilage and forcing stores to discard large quantities of food. The attack vector was the remote management capability built into Danfoss controllers, which maintenance firms use to manage refrigeration units across store locations. Multiple French retail chains were affected, including Les Mousquetaires. The incident highlights serious cybersecurity risks in industrial control systems used in retail and food supply infrastructure. This type of attack on operational technology (OT) can have significant physical and financial consequences. The event underscores the need for stronger access controls and security measures on remotely accessible ICS/SCADA devices.