Hackers triggered a massive cyberattack on French supermarkets that forced refrigerators in hundreds of stores to shoot up in temperature, spoiling tonnes of fresh and frozen food.

Major chains E. Leclerc, Intermarche and Cooperative U confirmed to AFP they suffered the attack, which Cooperative U’s chief executive described as “unprecedented”.

At least 300 shops of Intermarche or its Netto brand were targeted, along with more than 100 Cooperative U outlets and several E. Leclerc stores, the retailers said in separate statements.

Paris prosecutors confirmed the attack, which also hit other major chains and sparked fires in some locations.

Hackers remotely triggered defrosting systems

BFM TV said hackers “managed to remotely trigger the forced defrosting of the refrigeration systems in numerous stores”.

Branches that were affected will have to “throw away all of the products” that are fresh and frozen, Intermarche told AFP.

French retail sector news website jebosseengrandedistribution.fr said other retail giants Carrefour Market and Monoprix were affected, but the companies have yet to confirm this.

E. Leclerc confirmed to AFP “that a cyberattack affected one of its refrigeration equipment suppliers,” resulting in “repercussions on the operation of refrigeration systems in several stores”.

A source close to the issue said refrigeration control systems from Danish manufacturer Danfoss were targeted.

Outdated systems failed to receive security updates

Danfoss told AFP in a statement that most of the affected equipment was “legacy” products which “no longer receive software or security updates”.

It said its AK-SM800 and AK-SC355 fridge regulator systems were notably affected, with a version of the former using “outdated firmware”. It added that it had long advised supermarkets to update from those models. Danfoss gave no figures of how many systems were affected.

A person close to French Prime Minister Sebastien Lecornu said France’s cyber security agency had already identified “a vulnerability in software supplied by a Danish company and has contacted the vendor”.

“It is liaising with its European counterparts, as other countries may be affected,” and is seeking “to identify other French companies involved in order to alert them” and “prevent the spread”, the source added.

Investigation launched as food security concerns grow

The chief executive of Cooperative U, Dominique Schelcher, described the attack as “unprecedented” and confirmed the cyberattack had affected refrigeration systems since Sunday night.

“Targeting equipment essential to the preservation of fresh products and to the food supply of the French people is extremely serious and is unprecedented. It is unacceptable,” he wrote on X.

He added that the company’s teams were “fully mobilised” to restore the situation as quickly as possible.

“An investigation will be necessary to shed full light on this attack,” he added.

The office of the Paris prosecutor confirmed to AFP that an investigation has been opened into “the large-scale cyberattack affecting the refrigerators of several major food retail chains across France”.

The probe will help “identify the victims and establish the link with the damage they reported in terms of foodstuff losses and the outbreak of fires”, the prosecutor’s office said.

Intermarche condemned the food waste and financial losses resulting from the attack, without providing figures.

BFM TV said temperatures were “altered remotely, resulting in the destruction of stocks of fresh and frozen products”.

EU condemns attack on food systems

“Food security requires more attention at all levels,” said the EU’s food and agriculture commissioner Christophe Hansen on X, condemning the attack and saying such “exploitation of food” was now a “reality”.

The incident comes against the background of growing concern over the potential havoc that can be caused in Europe in all sectors by malicious actors carrying out cyberattacks.

President Emmanuel Macron, a strong supporter of Ukraine in its fight against the Russian invasion, last month ordered measures to protect France’s critical infrastructure from Russian “hybrid attacks”.

Industrial equipment such as refrigeration units, long isolated from the internet, are now connected via sensors or remote monitoring systems, Antoine Hautin of cybersecurity consultancy Almond told AFP.

By likely affecting hundreds of units at the same time, the attack demonstrated “a certain level of sophistication,” he added.

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