Kyushu Electric Power Co., Inc. has disclosed a physical security incident that affects private data of more than 10 million customers.
In an official announcement, the company explains that the IT staff regularly performs backups to manage server storage. Due to capacity constraints, on April 27 an external storage device was used for the task.
The drive was then stored in a server room cabinet protected by multiple physical security layers. On May 26, when IT staff went to retrieve it, they found the cabinet had been left unlocked and the driver was missing.
Kyushu Electric Power Company is one of Japan's major regional electric utilities, supplying electricity across the Kyushu region, which includes the prefectures of Fukuoka, Saga, Nagasaki, Kumamoto, Oita, Miyazaki, and Kagoshima.
The overall population of the Kyushu region is 12.6 million, and the company stated that the incident impacts up to 10.9 million accounts.
