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JAENES
BLeak confirmedSeptember 25, 2026 announced

キューサイ株式会社Data breach / unauthorized access incident

笹尾 祐太朗の写真Reviewed by Yutaro SasaoWritten by Leak Watch editorial team published ・ updated
Occurred on
Unconfirmed
Announced on
September 25, 2026
Severity
BIncidents centered on names and contact details.
Scale
484 people
Main impact
It was announced that a breach of a storage/delivery contractor led to the leak of the names, addresses, and phone numbers of 484 customers.
Information involved
Phone numberHome addressFull name
Cause / key point
Cause under investigation.About Supply chain attacks (via vendors & shared services)
Industry
Food & dining
Listing / capital
Unlisted
Sources
Last updated
October 20, 2026
Phone numberHome addressFull nameHow severity is assessed →

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Written & reviewed

笹尾 祐太朗の写真

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: Supply chain attacks (via vendors & shared services)(Compromising the provider instead of the user)

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