Egregor is a ransomware strain that exfiltrates data pre-encryption and then threatens to release sensitive information if a ransom is not paid. The attack is apparently based on the same system used in recent attacks on UbiSoft and Barnes & Noble. The strain appears to have grown rapidly as criminals turned to the system following the shutdown of the Maze ransomware operation, BleepingComputer reports. Kmart reportedly shut down access to certain back-end systems in the wake of the attack.”]
Source: https://www.darkreading.com/attacks-breaches/kmart-hit-by-egregor-ransomware