Hundreds of supermarkets in France were hit by a large-scale cyberattack on their refrigeration systems, causing the temperature in fridges and freezers to rise to 50 degrees Celsius. This resulted in massive food spoilage and several fire incidents at stores. Major French retail companies, including Intermarché, Coopérative U, E.Leclerc, and other organizations, confirmed the attack on Tuesday, describing it as unusual. According to the AFP news agency, at least 300 stores of Intermarché and its sub-brand Netto were targeted, while more than 100 centers of Coopérative U were affected. Carrefour stated that the effects of the cyberattack were seen in 80 of its supermarkets, while five percent of Monoprix’s approximately 490 stores were impacted. E.Leclerc also confirmed that several of its stores were targeted.

According to the Paris prosecutor’s office, the massive cyberattack affected the internet-connected refrigeration systems of several major food retail companies in France, leading to food losses and fire incidents. Following the attack, Prime Minister Sébastien Lecornu ordered the French National Cybersecurity Agency (ANSSI) to conduct an investigation. An official from his office told Reuters that France is in contact with European countries, as other nations may also be affected by the attack. Authorities are also checking whether other companies in France are at risk. Intermarché CEO Thierry Cotard told BFM TV that this unusual attack could result in losses of several hundred million euros across France in a single day.

According to TV reports, hackers remotely forced the refrigeration systems into defrost mode, destroying the stock of fresh and frozen food items. Intermarché told AFP that affected stores will have to discard all impacted fresh and frozen food items. Coopérative U CEO Dominique Schellinger said that the company’s refrigeration systems have been disrupted since Sunday night. He wrote on the social media platform X that targeting essential equipment for the protection of fresh food and the supply of food items to the public is extremely serious and unacceptable. He stated that the company’s teams are working to restore the systems to normal as quickly as possible and that investigations are necessary to uncover the full truth of the attack.

According to a source from Lecornu’s office, France’s cybersecurity agency has identified a vulnerability in the software provided by the Danish company Danfoss. Danfoss said it is aware of a limited number of incidents related to the management of refrigeration systems in France. According to the company, outdated firmware was being used in the affected devices. It stated that it has long advised users to keep their software updated and replace old devices. Cybersecurity company Clarity had identified such vulnerabilities in Danfoss’s systems in a study on August 9, through which attackers could bypass the security authentication process.

The French retail trade organization FCD has demanded full transparency from Danfoss. According to the organization, work has resumed in some of the affected stores.

Cyber threat analyst Félix Aime told Reuters that Spain, Portugal, Poland, Germany, and Belgium have also been affected by the attack. Cybersecurity analyst Steven Lauchlan said in an interview with Al Jazeera that attacks of this nature are not entirely new, but their occurrence on such a large scale is unusual. According to him, once a vulnerability in an internet-connected device is discovered, attackers can remotely access and control its functions. He said, “We are using basic systems that are directly connected to the internet and can be hacked. This is a new reality.” He described the incident as a significant warning sign on a global scale, stating that national and international measures are essential to prevent such attacks.

Lauchlan warned that although retail companies have incurred losses of millions of euros due to food spoilage this time, energy infrastructure or hospitals could also be targeted in the future.