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JAENES
SPartial leak confirmedOctober 22, 2026 announced

厚生労働省（1FEdu・テクノヒル）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
October 22, 2026
Severity
SCompromise of deep personal data or usable credentials.
Scale
595 people
Main impact
The 厚生労働省‑contracted online training site for radiation‑exposure reduction in decommissioning work, 1FEdu, operated by テクノヒル株式会社, was subject to a third‑party cyberattack that exposed 6 email addresses and passwords (credentials) and resulted in confirmed unauthorized logins using them; this may have led to the leakage of up to 595 participants’ records (including the 6) — name, furigana, age group, gender, affiliated organization, department, position, job type, email address, password, phone number, years of experience at 東京電力福島第一原子力発電所, and duties at time of registration (fields vary by registrant). The passwords were system‑assigned and could not be set or changed by users, so reuse on other systems is considered unlikely. No misuse or secondary harm has been confirmed to date, and the site has been suspended and blocked from external access while guidance to the contractor and individual notifications to affected persons proceed.
Information involved
Full nameEmail addressPasswordPhone number
Cause / key point
Third‑party cyberattack on the contracted operating site 1FEdu (credential leakage and unauthorized logins)About Abuse of credentials
Industry
Government & municipal
Listing / capital
Government / public body
Sources
Last updated
October 23, 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: Abuse of credentials(Logging in legitimately with leaked or guessed passwords)

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