Cyber attack again on European supermarkets; The temperature of the refrigerators reached 50 degrees The cooling systems of dozens of chain stores in Belgium and Luxembourg were the target of a cyber attack on Monday morning, and the temperature of their refrigerators and freezers rose. Stores in Sweden and Estonia reported similar problems. In some cases the temperature of the cooling equipment reached 50 degrees Celsius. It happened before in France. The identity of the hackers is still unknown.