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JAENES
BPossible leakAugust 3, 2026 announced

株式会社大仙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
August 1, 2026
Announced on
August 3, 2026
Severity
BIncidents centered on names and contact details.
Scale
Unknown
Main impact
Unauthorized external access (malware infection) caused a shutdown of all internal systems, disrupting order and shipping operations. Investigation is ongoing; no data leakage has been confirmed to date, but the scope is under investigation.
Information involved
Not specified in the disclosure
Cause / key point
Reported to be due to unauthorized external access (malware infection).
Industry
Manufacturing
Listing / capital
Unlisted
Sources
Last updated
October 20, 2026
How 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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