Cyberattack Exploits Exposed Danfoss Refrigeration Controllers Across French Supermarkets

A remote cyberattack allowed attackers to manipulate refrigeration systems in French supermarkets by targeting Danfoss controllers, raising temperatures through forced defrost cycles and forcing the disposal of perishable goods. The incident affected multiple retail chains, including Intermarché, Coopérative U, Carrefour Market, Monoprix, Leclerc, and Super U, impacting between 250 and 350 stores.

The attackers altered operational parameters on the AK-SM 8xxA Series controllers running outdated software, specifically activating automatic defrost cycles that rapidly increased temperatures in food display cases. In a retail food environment, such changes can render stock unsellable within hours. The Paris prosecutor’s office has launched an investigation into the large-scale cyberattack and is working to quantify losses from spoiled inventory and related incidents, including reported fires.

Exposed OT Interfaces and Known Vulnerabilities

Investigations point to a recurring OT weakness: internet-exposed web management interfaces on Danfoss controllers. Recent research identified three critical vulnerabilities in the AK-SM 8xxA Series:

• CVE-2025-41450 — authentication bypass in versions prior to 4.2, potentially leaking sensitive data such as internal IPs, store names, and user accounts via web reports.
• CVE-2025-41451 — command injection leading to remote code execution after authentication in versions before 4.3.1.
• CVE-2025-41452 — ability to inject Nginx configuration directives after authentication, enabling denial-of-service conditions in versions prior to 4.3.1.

Scans have identified thousands of Danfoss management interfaces reachable from the internet, with 2,752 systems exposed globally and 1,590 located in France alone. More than 4,500 devices are discoverable through connected asset search engines.

Recommended Defensive Actions

Organizations using these controllers should immediately inventory all Danfoss devices, identify any exposed web consoles, and restrict them from direct internet access. Remote management must route through VPNs and trusted administrative networks with strict source-based access controls. Systems should be updated to version 4.2 or higher to address CVE-2025-41450 and to 4.3.1 or higher to mitigate CVE-2025-41451 and CVE-2025-41452.

Additional OT hygiene measures include network segmentation between IT and OT environments, hardened credentials, auditing of administrative access, and change logging. Temperature monitoring should specifically alert on anomalous readings, unexpected defrost cycles, and configuration modifications. Contingency procedures for preserving the cold chain remain essential when other controls fail.