Federal agencies warned Thursday of an ongoing cyber threat to industrial refrigeration systems used across critical infrastructure sectors including food and agriculture, healthcare, transportation, and chemicals.

The Cybersecurity and Infrastructure Security Agency, FBI, Department of Health and Human Services, Department of Agriculture, and Department of Transportation released a fact sheet detailing malicious cyber activity targeting vulnerabilities in internet-accessible electronic temperature controllers and commercial refrigeration controllers. These devices are common in retail grocery stores and cold storage facilities.

If exploited, attackers could alter temperatures, force units into continuous heating or defrost cycles, create fire hazards, spoil inventory, shorten equipment life, or block operators from monitoring conditions. The agencies said every organization relying on refrigeration and monitoring systems should assume it is a potential target.

The alert follows multiple waves of cyberattacks on commercial freezers and fridges in the United States and Europe in recent months. Incidents have affected supermarkets, military commissaries, and at least one blood bank facility in France.

CISA Acting Executive Assistant Director for Cybersecurity Chris Butera stated that organizations should review the guidance and close known security gaps immediately. FBI Cyber Branch Operations Director Brett Leatherman noted that the government is seeing these systems targeted across critical infrastructure sectors globally.

The agencies recommended several immediate steps for operators: remove control system devices from the public internet, change default passwords and use strong authentication, apply patches and updates promptly, identify and replace unsupported legacy devices, and secure any necessary remote access behind firewalls.

The warning underscores vulnerabilities in systems that protect food supplies, medicines, and other temperature-sensitive goods. Officials urged owners and operators in affected sectors to act without delay to reduce risks to public safety and economic stability.