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JAENES
SPartial leak confirmedMarch 26, 2026 announced

株式会社JEMSData 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
March 26, 2026
Severity
SCompromise of deep personal data or usable credentials.
Scale
223 records
Main impact
Unauthorized sign-ins to employee email resulted in illicit access from overseas, and 223 phishing emails were sent externally. The number of affected individuals is unknown.
Information involved
Auth token
Cause / key point
While authentication credentials, etc. may have been exfiltrated, the cause had not been identified as of 3月26日.About Targeted email & phishing
Industry
Services & other
Listing / capital
Unlisted
Sources
Last updated
October 20, 2026
Auth tokenHow 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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