花キューピット株式会社Data breach / unauthorized access incident
- Occurred on
- October 14, 2026
- Announced on
- October 28, 2026
- Severity
- CLimited data such as email addresses and identifiers.
- Scale
- 4,238,242 records
- Main impact
- Due to unauthorized access to the management system of the operated e-commerce site, up to 4,238,242 member records (login IDs, encrypted passwords, and email addresses) may have been leaked. It is stated that sensitive information such as names, addresses, and card numbers were not included.
- Information involved
- Email addressUser / member IDPassword
- Cause / key point
- Unauthorized access by a third party to the company’s management system (the intrusion route and attack method are not disclosed in the published information).
- Industry
- Retail & e-commerce
- Last updated
- October 29, 2026
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Written & reviewed
Reviewed byYutaro SasaoFounder & CEO, MediaLeap Inc.
CEO of MediaLeap Inc. Working on both sides of web advertising and web media since 2013; founded the company in May 2025.
Review scope: cross-checking against primary sources (official and government announcements), verifying claims stay within the facts, and checking source attribution。Last reviewed:
Written by:Leak Watch editorial team (AI-assisted drafts verified against sources by the editorial team) · Reviewer profile · Request a correction
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Attack method classification: Unauthorized access (method undisclosed)(Breached, but the technique was not identified or disclosed)
Read the Unauthorized access (method undisclosed) guide and national trends →