[Investigating][Severity: Major][Intrusion]

Kyushu Electric Power Transmission and Distribution: intrusion may have leaked 4,139 electricity usage records

An intrusion may have leaked 4,139 records of electricity use or sales with supply point numbers, without names. The usage inquiry service is stopped.

Disclosed

2026-11-05

Organizations involved

Leaked or at risk

4.1K

4,139

Downtime

Unknown

What happened

2026-10-30
Kyushu Electric Power Transmission and Distribution Co., Inc. detected unusual errors in a system and, as unauthorized access looked possible, shut that system down. [1]
2026-11-02
Server logs showed that data may have left the company, and it reported to the Personal Information Protection Commission and its regulator. [1]
2026-11-05
It disclosed the possible leak and the partial service stop. [1]

Impact

4,139 records may have leaked: electricity consumed or sold (monthly and 30-minute values) with the number identifying each supply or receiving point. Names, addresses, phone numbers, email addresses, accounts and other contract details were not included. Affected customers will be told individually around mid-November. [1]

The system was taken off the network, so the Electricity usage and charge inquiry service used by customers on remote islands and by those selling power is stopped. Recovery is being planned, and power supply is not affected. [1]