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JAENES
BPartial leak confirmedSeptember 1, 2026 announced

株式会社TRUNKData 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 1, 2026
Severity
BIncidents centered on names and contact details.
Scale
424 records
Main impact
Unauthorized access to employee email led to some held information being leaked externally, and suspicious emails impersonating employees were sent. The number of potentially affected records is 424.
Information involved
Email addressHome addressFull name
Cause / key point
Cause under investigation.
Industry
Services & other
Listing / capital
Unlisted
Sources
Last updated
October 20, 2026
Email addressHome 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: Unauthorized access (method undisclosed)(Breached, but the technique was not identified or disclosed)

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