Kyushu Electric Power Co. has disclosed a data breach affecting up to 10.9 million customers after an external storage drive containing backup data went missing from a server room cabinet. The drive, used on April 27 due to storage capacity constraints, was found missing on May 26 when staff went to retrieve it. The cabinet had been left unlocked. Exposed data includes customer names, addresses, electricity usage data, and phone numbers, though no financial data was stored on the drive. The company filed a police report on June 4, interviewed all 57 personnel with server room access, and has been unable to locate the drive. Japan's Ministry of Economy, Trade, and Industry has given the firm until July 8 to report full details and preventative measures.
