French blood agency ( EFS ) confirmed on Wednesday that French blood banks were affected by a recent wave of cyberattacks targeting European cooling systems on Monday.

The institution stated that although it was not the direct target of this attack, on three of its sites, the refrigeration equipment used by external service providers to store EFS blood products was compromised, and hackers raised the temperature of the equipment.

EFS stated in a declaration: 'Specifically, the temperature and defrosting thresholds have been set at excessively high levels.' CNBC translated this declaration from French to English.

It is stated that: 'These refrigeration devices are located at the preparation and distribution sites of EFS, and are used to store blood products before delivery to medical institutions, as well as to hold samples for use by the EFS biological sample bank.'

These devices also store frozen plasma used for blood transfusions, as well as frozen plasma used in pharmaceutical production.

EFS indicates that its monitoring system was quickly triggered. Depending on the specific circumstances, the affected devices were either re-controlled without any impact on the products or samples, or they were taken offline for processing. EFS adds that this attack did not result in any loss of samples or blood products, and the relevant samples were promptly transferred to other facilities.

EFS is currently coordinating with the French National Cybersecurity Agency (ANSSI) and the French Ministry of Health, and has also strengthened monitoring of devices.

Hundreds of supermarkets in France and other European countries (including Belgium, Sweden, and Finland) have previously experienced remote intrusions into their refrigerators, with the temperatures being raised, which could have led to the spoilage of food worth millions of euros.