Overview
Jiho and Jiho Business Service jointly disclosed one incident. Up to 890 email-address entries may be involved, not an established count of 890 people; the numeric field is NULL because this is a maximum. Occurrence and discovery dates are unknown. Outgoing phishing messages do not establish the initial entry method.
Timeline
- Occurred
- Discovered
- Disclosed
Joint notice disclosed possible exposure.
Organization response
The group blocked the unauthorised access route, investigated and reviewed controls. It contacted owners of addresses to which suspicious messages were sent.
What you can do
Check notices through the organisation’s genuine contact channels. Do not enter credentials or payment details through links in unexpected messages.
Sources
- クラウドメールへの不正ログインに関する報告じほう・じほうビジネスサービス · 2026-11-09