Coolworld, a specialist supplier to the French blood service (EFS), was hit by a cyber attack that attempted to destroy blood stocks by heating them to over 110ºC.
According to , in the early hours of Monday 2 November 2026 the cold stores that normally house donated blood at -30ºC were accessed by cyber criminals and programmed to reach a temperature that would very literally leave blood boiling.
The targeted storage units contained blood that was being kept as part of a health monitoring system related to blood transfusions, as well as plasma that was intended for donation.
An anonymous source working for Coolworld told that if blood were to get that hot it would “destroy the antibodies”, meaning it could no longer be used for transfusion.
A surgeon put it more bluntly: “At that temperature, it would be black pudding!”
A spokesperson for the EFS told : “An on-call technician noticed on Sunday night going into Monday morning that the temperature in the cold store was rising.”
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The French ministry of health added that there has been “no operational consequences, as the situation was recognised (as it was happening).”
A rolling wave of attacks
The revelations come as supermarkets across continental Europe have been hit by ruinous cyber attacks over the course of the past 10 days. The cost of the damage across France, Belgium, the Netherlands, Sweden, Estonia, and Finland is in the millions of Euros so far.
In each instance, the method of attack has been the same: in the early hours of the morning on a Monday, attackers have targeted industrial fridges and freezers, including cold stores, and set the units to heat, rather than cool.
In the case of the first wave of French attacks, the targeted units were no longer receiving software updates and security patches from the manufacturer. It hasn’t been confirmed whether this is the case in the attacks this week.
In addition to the attacks in continental Europe, some meat distributors in the UK have also been affected.
Tony Goodger, head of communications at the Association of Independent Meat Suppliers (AIMS), told : “When hackers have decided to target European supermarkets … a few of our 300+ members who operate the same software have unexpectedly become ‘collateral’ within the hack.
“None who have been affected have lost any meat but, once again, this must act as a reminder to all in the food industry at whatever point in the supply chain they are that their businesses may be seen by some as targets. We urge our members and the wider industry to be vigilant.”
Chris Dimitriadis, chief global strategy officer at ISACA, said the issue goes beyond supermarket refrigeration. “Operational technology is used to monitor and control physical processes in sectors such as energy, water, manufacturing, and transport and when it is compromised the effects are felt immediately in the physical world.”
“The risks and consequences vary and when critical infrastructure is involved, human life is at stake,” he added.