Cyberattacks Defrost Freezers at Supermarkets in Sweden and Belgium

Dozens of supermarkets in Sweden and Belgium have been targeted in cyberattacks that sent freezer and refrigerator temperatures soaring overnight, putting large quantities of food at risk.

The incidents follow a major attack in France last month, when hackers reportedly gained access to cooling systems at hundreds of supermarkets, leading to food waste and several fires.

One Swedish supermarket said on social media Monday that its refrigerators and freezers had been reset to 50 degrees Celsius—a temperature setting similar to that reported during the French attack.

“We are aware that a limited number of stores were affected by an incident overnight, which impacted their refrigeration and freezer systems,” a spokesperson for privately owned retailer ICA said in an email.

Grocery chain Coop told Swedish newspaper Aftonbladet that six of its stores had experienced similar problems.

Coop did not immediately reply to a request for further comment.

Sweden’s national cyber-security centre said it was investigating several incidents involving refrigeration equipment at grocery stores around the country.

Local media reported that dozens of refrigerators and freezers at Delhaize supermarkets in Belgium and Luxembourg were also affected by the cyberattack.

Delhaize and butcher chain De Laet & Van Haver both said their cooling systems had suddenly registered sharply elevated temperatures.

Carrefour Belgium added Monday morning that 15 of its stores had been affected so far.

France’s National Cybersecurity Agency is continuing to investigate the earlier attack on supermarkets across the country.

French authorities have been sharing information with European counterparts amid concerns that the same campaign may have reached other countries.

In France, Carrefour said 80 of its supermarkets had been affected, while Monoprix—which operates roughly 490 ​stores—reported that 5 per cent of its outlets were hit.

Les Mousquetaires, the group behind Intermarché, said refrigeration units at approximately 150 of its ⁠stores had been raised to 50 C for six hours during the night.

The company said all potentially affected products were destroyed as a precaution to protect customers from food-safety risks.

Images from the scene showed supermarket workers emptying carts packed with thawed frozen goods into a large waste container. Melted ice cream spilled from damaged tubs onto the pavement.

While no overall estimate of the damage was available, Intermarché chief executive Thierry Cotillard told BFM TV that the “unprecedented” attack could cost the industry “tens ​of millions of euros nationwide in a single day.”

Cold-storage systems in supermarkets are commonly operated through control panels that regulate an entire store’s refrigerators and freezers. Because those systems can be connected to the internet, maintenance providers are often able to access and adjust them remotely.

The source ‌close to the investigation said ANSSI had identified a vulnerability in software supplied by Danish company Danfoss.

Danfoss said it was ‘aware of incidents in France affecting a limited number of refrigeration management systems’.

The affected units ‘were running outdated firmware’, Danfoss said, adding that it had ‘long advised customers to keep supported systems updated with the latest firmware and to migrate legacy systems to current-generation solutions’.

The ​attacks resemble disruptions reported at about a ⁠dozen US military commissaries in late August that led to food losses after fridges were affected.

In a statement, French retail association Fédération du Commerce et de la Distribution called for ‘full transparency’ from Danfoss about the incident. 

It said supermarkets aimed to protect consumers and return to ​normal operations as soon as possible. The FCD said some impacted stores were already back up and running.