株式会社D&MData breach / unauthorized access incident
- Occurred on
- Unconfirmed
- Announced on
- June 12, 2026
- Severity
- BIncidents centered on names and contact details.
- Scale
- 633 records
- Main impact
- A fax storage server was infected with ransomware, and it is highly likely that 633 records including customers' and business partners' names, addresses, and phone numbers were leaked. This is a case with a high risk of personal information disclosure.
- Information involved
- Phone numberHome addressFull name
- Cause / key point
- A fax storage server was infected with ransomware.About Ransomware
- Industry
- Services & other
- Listing / capital
- Listed company東証グロース 189A(D&Mカンパニー)
The listed company is D&Mカンパニー
- Last updated
- October 20, 2026
Stock price reaction to the disclosureD&Mカンパニー / 東証グロース 189A
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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: Ransomware(Encrypting data and demanding a ransom)
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