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JAENES
BLeak confirmedMarch 6, 2026 announced

株式会社マリモホールディングス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
December 18, 2025
Announced on
March 6, 2026
Severity
BIncidents centered on names and contact details.
Scale
1,360 people
Main impact
It was announced that employee information was illicitly obtained via phishing that impersonated executives, and approximately 1360 employees were affected.
Information involved
Email addressUser / member IDFull name
Cause / key point
Illicit acquisition of information through phishing impersonating executives.About Targeted email & phishing
Industry
Services & other
Listing / capital
Unlisted
Sources
Last updated
October 20, 2026
Email addressUser / member IDFull nameHow severity is assessed →

Is this incident worth paying attention to?

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: Targeted email & phishing(Fake emails and sites that steal credentials)

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