Présentation
Affected: mail services of STNet, KDDI Web Communications (CPI), JCOM, Chubu Telecommunications, NIFTY and BIGLOBE. The July 6 report (updated July 21) confirmed email addresses of 12,231,954 people leaked, including passwords of 7,616,173 (a subset). au-branded mail runs on separate systems and was unaffected. The Ministry of Internal Affairs and Communications ordered a report on June 24. Each ISP's impact is recorded separately and must not be summed.
Chronologie
- Survenue
- Découverte
- Divulgation
Intrusion found; system patched.
Announced (up to 14.22M possibly affected).
Report filed; confirmed counts published.
Réponse de l’organisation
Per the notice, the organisation investigated and contained the incident, notified individuals and offered monitoring or protective resources.
Que faire ?
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
- ISP事業者向けメールシステムに対する不正アクセスの発生についてKDDI株式会社 · 2026-11-09
- KDDI株式会社に対する報告徴収総務省 · 2026-11-09
- ISP事業者向けメールシステムに対する不正アクセスについてのお詫びとご報告KDDI株式会社 · 2026-11-09