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JAENES
BPossible leakMay 7, 2026 announced

株式会社イースト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 7, 2026
Severity
BIncidents centered on names and contact details.
Scale
Unknown
Main impact
Unauthorized access to the internal network was confirmed. The company is investigating with the police and external experts, and at the time of the announcement no data leakage has been confirmed.
Information involved
Not specified in the disclosure
Cause / key point
The cause is under investigation.
Industry
Services & other
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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