ビックカメラ、コジマ、ソフマップData breach / unauthorized access incident
- Occurred on
- October 28, 2023
- Announced on
- November 2, 2023
- Severity
- CLimited data such as email addresses and identifiers.
- Scale
- 14,900,000 records
- Main impact
- Unauthorized access to the outsourced email-delivery service may have leaked customer information (mainly email addresses) for three companies totaling 約1,490万件; the outsourcing provider 委託先アララ as a whole could be affected for 約7,700万件.
- Information involved
- Email address
- Cause / key point
- Unauthorized access to the vendor's system that exploited a web server vulnerability and weaknesses in the system environment.About Exploitation of vulnerabilities
- Industry
- Retail & e-commerce
- Last updated
- November 4, 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 →