ミカサData breach / unauthorized access incident
- Occurred on
- April 21, 2026
- Announced on
- June 16, 2026
- Severity
- BIncidents centered on names and contact details.
- Scale
- 4,298 people
- Main impact
- Between 2013-09 and 2016-03, up to 4,298 individuals who purchased from the online shop may have had portions of their personal information—names, addresses, e-mail addresses, phone numbers, dates of birth, etc.—leaked externally.
- Information involved
- Email addressPhone numberHome addressFull nameDate of birth
- Cause / key point
- Disposed PC terminals were not sufficiently damaged in specific areas, leaving some data intact while they circulated, and a third party obtained them.
- Industry
- Manufacturing
- Listing / capital
- Unlisted
- Sources
- Last updated
- October 20, 2026
Is this incident worth paying attention to?
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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Incidents related to "オンラインショップ"
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Same industry
- SS精電舎電子工業2026.07.21 announced・Affected Unknown
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Attack method classification: Under investigation / not stated(Cause not disclosed)
Read the Under investigation / not stated guide and national trends →