株式会社トーホーData breach / unauthorized access incident
- Occurred on
- March 31, 2026
- Announced on
- April 7, 2026
- Severity
- BIncidents centered on names and contact details.
- Scale
- 1 people
- Main impact
- It was announced that the email account of 1 employee was misused. There is no information on the number of affected records.
- Information involved
- Email addressUser / member ID
- Cause / key point
- The cause is under investigation.
- Industry
- Services & other
- Listing / capital
- Listed company東証プライム 8142(トーホー)
- Last updated
- October 20, 2026
Stock price reaction to the disclosureトーホー / 東証プライム 8142
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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: Under investigation / not stated(Cause not disclosed)
Read the Under investigation / not stated guide and national trends →