長崎市（屋外広告物申請書の誤送付）Data breach / unauthorized access incident
- Occurred on
- May 29, 2026
- Announced on
- October 6, 2026
- Severity
- CLimited data such as email addresses and identifiers.
- Scale
- 1 people
- Main impact
- When sending a notice about the outdoor advertising permit renewal to another corporation, a different corporation's application was mistakenly enclosed, and the name of one person was disclosed externally.
- Information involved
- Full name
- Cause / key point
- The cause is under investigation.
- Industry
- Government & municipal
- Listing / capital
- Government / public body
- 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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Attack method classification: Under investigation / not stated(Cause not disclosed)
Read the Under investigation / not stated guide and national trends →