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OT/ICS Cyberattack Spoils Food Stocks by Hijacking Supermarket Refrigeration Systems

Attackers exploited vulnerabilities in legacy industrial control software from Danfoss to manipulate refrigeration defrost cycles, driving temperatures to 50°C and causing millions of euros in food spoilage losses. The root problem lies in operational technology (OT) systems — refrigeration controllers, HVAC, and similar industrial devices — being reachable over networks without adequate isolation from corporate IT environments or the internet. Older control software in critical infrastructure is frequently unpatched and unmonitored, creating a wide attack surface that is attractive to threat actors seeking physical, financial, or disruptive impact. This incident underscores that cyberattacks are no longer confined to data theft; they can cause direct physical and economic harm to essential supply chains.

Tactical Insight

Immediate actions

  • Audit and isolate all OT/ICS devices (refrigeration controllers, HVAC, PLCs) from corporate IT networks and the public internet immediately.
  • Inventory all industrial control software versions and apply available patches or vendor mitigations, prioritising legacy systems like the affected Danfoss software.
  • Change all default credentials on OT devices and enforce strong authentication for remote access.

Long-term improvements

  • Implement strict network segmentation using DMZs and industrial firewalls to separate OT environments from IT networks and external connectivity.
  • Establish a dedicated OT/ICS vulnerability management programme that tracks EOL software and firmware across all vendor-supplied control systems.
  • Develop and regularly test an OT-specific incident response plan that includes procedures for physical asset protection (e.g., manual temperature overrides, backup cooling protocols).

Detection measures

  • Deploy OT-aware monitoring tools (e.g., Claroty, Dragos, Nozomi) to detect anomalous commands or parameter changes in industrial control systems.
  • Set automated alerting thresholds on critical physical parameters such as refrigeration temperature deviations beyond acceptable ranges.
  • Require vendors like Danfoss to provide a Software Bill of Materials (SBOM) and timely security advisories for all deployed control software.

Back this up with a control

All controls and vendors

Training helps people spot this. These controls make the attack fail even on the day someone does not.