ディーエイチシー（DHC）Data breach / unauthorized access incident
- Occurred on
- October 28, 2026
- Announced on
- October 30, 2026
- Severity
- AFinancial and HR records — information that easily translates into monetary damage.
- Scale
- 5,096 accounts
- Main impact
- Unauthorized third-party access to the official online shop resulted in 5,096 accounts having their member information altered, and stored member numbers, names, addresses, phone numbers, purchase histories, and the last four digits of credit card numbers may have been viewed; reports state they have restored altered accounts and canceled suspicious orders.
- Information involved
- User / member IDFull nameHome addressPhone numberCard & payment data
- Cause / key point
- The company disclosed that member information was altered due to unauthorized third-party access, and media reports indicate external unauthorized access altered member data; they reportedly severed communications and addressed vulnerabilities.About Exploitation of vulnerabilities
- Industry
- Retail & e-commerce
- Listing / capital
- Unlisted
- Sources
- Last updated
- November 1, 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: Exploitation of vulnerabilities(Breaking in through holes in software and devices)
Read the Exploitation of vulnerabilities guide and national trends →