Hacked Fridges and Freezers: US Agencies Urge Operators to Lock Down Cooling Systems

The US Cybersecurity and Infrastructure Security Agency (CISA), the FBI and other agencies have urged critical infrastructure operators to protect their cooling systems. The warning follows attacks in which hundreds of supermarkets across Europe had their refrigerators remotely hacked and temperatures raised, potentially spoiling millions of euros of food. Separately, cooling unit controls were tampered with at three of France's national blood banks, though it is unclear whether those incidents are linked.

The advisory explains that healthcare, transportation, food and chemicals organisations widely use cooling systems with automated and remote monitoring. Attackers may exploit unpatched or internet-accessible controllers to change settings and force units into continuous heating and defrost cycles, which can cause widespread inventory loss and equipment hazards. In August, freezers and refrigeration units at several US military commissaries also switched into defrost or heating modes, though no connection to the European attacks has been established. The Defense Department's inspector general is investigating. No one has claimed responsibility for the European attacks. Authorities remain on high alert for hybrid threats amid tensions with Russia, which has repeatedly denied involvement in sabotage operations.

The agencies recommend using strong authentication, keeping systems updated, identifying any systems reachable from the internet, removing unnecessary remote access, and securing any remote access that is needed.