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JAENES
BLeak confirmedJanuary 21, 2026 announced

株式会社cocoloniData 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
November 27, 2025
Announced on
January 21, 2026
Severity
BIncidents centered on names and contact details.
Scale
Unknown
Main impact
They reported there was unauthorized access from 2025-11-27 to 2025-12-13, and on 2025-12-13 they became aware of the leakage of email addresses and encrypted passwords.
Information involved
Email addressPassword
Cause / key point
The cause is under investigation.
Industry
IT & telecom
Listing / capital
Unlisted
Sources
Last updated
October 20, 2026
Email addressPasswordHow 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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