Poorly secured refrigeration controllers led to spoilage and fires in French supermarkets

The attack shows how weak controls in remote refrigeration systems can turn a store IT problem into damaged stock and fire risk.

A mass compromise of internet-connected refrigeration controllers appears to have disrupted about 700 supermarkets in France, leading to spoiled inventory and, in some cases, electrical fires. French authorities said the attackers got into store-wide refrigerator and freezer systems through remotely managed controllers, then drove defrost cycles long enough to push temperatures as high as 50°C. Security research had already identified critical flaws in the affected controller lines from Danfoss, Dixell, and Copeland, including remote-login access with administrator-level rights. One Danfoss design also relied on a daily password derived from publicly available firmware, which means anyone who reverse-engineers the code can reproduce it on unpatched devices.