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JAENES
BPossible leakMay 12, 2026 announced

日本・アルカディア・ネットワーク株式会社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
May 12, 2026
Severity
BIncidents centered on names and contact details.
Scale
Unknown
Main impact
Traces of unauthorized access and suspicious files were found on some customer servers we manage, confirming unauthorized access; the number of affected individuals and incidents is not listed in the public materials.
Information involved
Not specified in the disclosure
Cause / key point
The cause is under investigation.
Industry
IT & telecom
Listing / capital
Unlisted
Sources
Last updated
October 20, 2026
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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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