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JAENES
BPossible leakNovember 9, 2026 announced

大阪市（児童いきいき放課後事業）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
January 1, 2026
Announced on
November 9, 2026
Severity
BIncidents centered on names and contact details.
Scale
415 people
Main impact
Due to the outsourced contractor falling victim to a support scam, personal data for up to 415 individuals may have been exposed — 213 child users, 168 guardians, and 34 staff — including names, dates of birth, addresses, and phone numbers. No fraudulent use has been confirmed as of now.
Information involved
Full nameDate of birthHome addressPhone number
Cause / key point
An outsourced contractor was targeted by a support scam that displayed false warnings on computer screens to fraudulently obtain money, which may have caused the user data leak.About Supply chain attacks (via vendors & shared services)
Industry
Education
Listing / capital
Government / public body
Sources
Last updated
November 10, 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: Supply chain attacks (via vendors & shared services)(Compromising the provider instead of the user)

Read the Supply chain attacks (via vendors & shared services) guide and national trends →

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