Hackers raise temperatures at French blood banks amid wave of refrigeration attacks in Europe

France's public blood transfusion operator, the French blood service (EFS), said its contractors' cold storage facilities were accessed by hackers who raised temperature and defrosting thresholds to "very high levels". The intrusion was detected by alarm systems, allowing technicians to intervene before any blood products were compromised. The affected sites stored plasma, platelets and other blood components used by more than 1,900 hospitals nationwide.

The incident occurred overnight on Monday and coincided with a broader series of cyber attacks on refrigeration equipment across Europe, which have also impacted supermarkets and other commercial cold stores. Authorities in several countries, including Italy, Germany, Romania and the United Kingdom, reported similar disruptions.

"These are not isolated incidents and of course we have to be collectively resilient and prepared for such cyber incidents," said Thomas Regnier, an EU spokesperson, adding that agencies were holding urgent discussions with national authorities.

EFS confirmed that the compromised blood products were transferred to other locations and that France's national cybersecurity agency (ANSSI) and the health ministry had been notified. Monitoring of all equipment has been intensified.

Cybersecurity firm Sophos senior director for threat intelligence Rafe Pilling suggested the most plausible explanations were a "state-based signalling and demonstration of capability" or a lone-wolf hacker, noting that no group has claimed responsibility.

The attacks highlight vulnerabilities in internet-connected refrigeration systems, which can be remotely monitored and controlled if software patches are not applied. Experts warn that such weaknesses could be exploited in future incidents.