九州電力送配電（外部記憶媒体）Data breach / unauthorized access incident
- Occurred on
- Unconfirmed
- Announced on
- July 8, 2026
- Severity
- SCompromise of deep personal data or usable credentials.
- Scale
- Unknown
- Main impact
- An external storage medium containing subscriber information and power usage records in 30-minute intervals is missing; external leakage has not been confirmed.
- Information involved
- Not specified in the disclosure
- Cause / key point
- Inadequate handling of external storage media and insufficient supervision of contractors.About Supply chain attacks (via vendors & shared services)
- Industry
- Services & other
- Listing / capital
- UnlistedParent company: キューデンホールディングス(東証プライム 642A)
In October 2026, 九州電力 became a holding company. 九州電力送配電 is its subsidiary.
- Last updated
- October 20, 2026
Stock price reaction to the disclosureキューデンホールディングス・親会社 / 東証プライム 642A
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CEO of MediaLeap Inc. Working on both sides of web advertising and web media since 2013; founded the company in May 2025.
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Attack method classification: Supply chain attacks (via vendors & shared services)(Compromising the provider instead of the user)
Read the Supply chain attacks (via vendors & shared services) guide and national trends →