Hokkaido Electric Power reports 5,664 email addresses leaked in October Arara cyber-attack
SpilloverSpillover from the Arara incident · View original incident →Hokkaido Electric Power announced on 13 November that unauthorised access to the external email delivery service “Arara Message” between 27 and 31 October 2026 had exposed 5,664 customer email addresses from its e-commerce site “Kirameku Store”. Names, addresses, telephone numbers, passwords and credit card information were not exposed. The company disconnected its site from the service and advised customers to watch out for suspicious emails.
Key facts
- Affected organisation
- Hokkaido Electric Power
- Original incident
- Arara email service cyber-attack exposes 81.33 million email addresses
- Incident type
- Data breach
- Occurred / detected
- 2026-10-27
- Scale of damage
- 5,664 email addresses
- Cause / method
- Unauthorised access to Arara
- Location
- Japan
If your data was exposed
Exposed dataEmail
- Don’t tap links in texts, calls or emails that mention this incident and offer compensation, refunds or breach checks. Check directly on the organisation’s official website or app.
Timeline
- It became known that unauthorised access to Arara had exposed 5,664 email addresses from Hokkaido Electric Power’s e-commerce site.
Original incident
This is spillover from the Arara incident.
Arara email service cyber-attack exposes 81.33 million email addresses
81.3mImpact: 81,329,467 email addresses and some customers' member information
Japan's Arara Message email delivery service was breached through a web server vulnerability, exposing email addresses and some customers' member information. Further investigation put the number of unique email addresses exposed at 81,329,467. The attacker also misused the service to send up to approximately 7.13 million emails impersonating credit card companies, and the company isolated the servers and suspended its email delivery service entirely.
Related reports: 20 · last report →
1 related reports
The summary and key facts are written by AI from related reports and may contain errors. Check the original articles and the organisation’s official statements for accurate details.