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JAENES
APossible leakFebruary 5, 2026 announced

アデコ株式会社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
February 5, 2026
Severity
AFinancial and HR records — information that easily translates into monetary damage.
Scale
Unknown
Main impact
It was announced that email accounts for the freelance business were accessed without authorization and emails were sent at random.
Information involved
Email addressUser / member ID
Cause / key point
The cause is under investigation.
Industry
Services & other
Listing / capital
Unlisted

Adecco Group's Japan subsidiary

Sources
Last updated
October 20, 2026
Email addressUser / member IDHow 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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