一宮市（アルカディア提供のメール配信・Net119等）Data breach / unauthorized access incident
- Occurred on
- Unconfirmed
- Announced on
- October 14, 2026
- Severity
- AFinancial and HR records — information that easily translates into monetary damage.
- Scale
- Unknown
- Main impact
- 一宮市 announced that due to unauthorized access to アルカディア, registration information for multiple services including email distribution, staff safety confirmations, and Net119 may have been exposed, and some new registrations were suspended; specific confirmed leaks follow the main text.
- Information involved
- Email addressPhone numberHome addressFull name
- Cause / key point
- Cause is under investigation.
- Industry
- Government & municipal
- Listing / capital
- Government / public body
Administrative services of 一宮市
- Last updated
- October 20, 2026
Is this incident worth paying attention to?
Written & reviewed
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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Incidents related to "net119"
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Same attack method
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Same industry
- S市立岸和田市民病院（患者書類）2026.10.16 announced・Affected 1 people
- S神奈川県警（使用済み運転免許証）2026.10.09 announced・Affected 30 records
- S長崎市（マイナンバーカード特急発行書類の紛失）2026.09.08 announced・Affected 4 people
- S村田製作所2026.04.27 announced・Affected 73,000 records
- S静岡市2026.01.30 announced・Affected 3,950 people
- A青森市（公民連携ポータルサイト）2026.10.19 announced・Affected 11 records
Attack method classification: Unauthorized access (method undisclosed)(Breached, but the technique was not identified or disclosed)
Read the Unauthorized access (method undisclosed) guide and national trends →