講談社BECK（旧ビーシーのメール）Data breach / unauthorized access incident
- Occurred on
- September 14, 2026
- Announced on
- October 2, 2026
- Severity
- SCompromise of deep personal data or usable credentials.
- Scale
- 1 records
- Main impact
- Continuous unauthorized access to one 旧ビーシー employee email account and traces of email data acquisition were confirmed, and it was reported that 50 spam emails were sent from that account.
- Information involved
- User / member IDPassword
- Cause / key point
- The cause is under investigation.
- Industry
- Retail & e-commerce
- Listing / capital
- Unlisted
講談社BECK is not publicly listed.
- Last updated
- October 20, 2026
Is this incident worth paying attention to?
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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: Unauthorized access (method undisclosed)(Breached, but the technique was not identified or disclosed)
Read the Unauthorized access (method undisclosed) guide and national trends →