Overview
Counts and fields are under investigation (count blank). Data feeds were stopped and delivery switched. Per the company, this stems from unauthorised access to the Arara email-delivery platform (recorded separately); this figure is a subset of the vendor scope and must not be added to it.
Timeline
- Occurred
- Discovered
- Disclosed
Organization response
Per the notice, the organisation investigated and contained the incident, notified individuals and offered monitoring or protective resources.
What you can do
Be wary of emails, SMS or calls impersonating the organisation; do not open links or attachments or enter passwords or card details. Change reused passwords on other services.
Sources
- 委託先メール配信サービスへの不正アクセスによる個人情報漏えいに関するお知らせとお詫び（第１報）株式会社学研ホールディングス · 2026-11-09