The attack, which has been confirmed by prosecutors in Paris, affected several large retail chains, including Intermarché, which owns Netto stores.
According to French broadcaster BFM TV, the hackers reportedly managed to "activate the defrost systems in a large number of stores."
Dominique Schelcher, CEO of the Coopérative U group, wrote in a post on X that the attack had affected the group since Sunday evening and described the incident as "extremely serious" and "unprecedented."
He was backed by EU Agriculture Commissioner Christophe Hansen, who also condemned the attack on X, stating that "food safety requires more attention at all levels."