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SLeak confirmedSeptember 8, 2026 announced

長崎市（マイナンバーカード特急発行書類の紛失）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
July 7, 2026
Announced on
September 8, 2026
Severity
SCompromise of deep personal data or usable credentials.
Scale
4 people
Main impact
Documents related to expedited issuance applications for My Number Card were lost, and documents for 4 people are unaccounted for. No Individual Number (my number) was recorded.
Information involved
Card & payment data
Cause / key point
Loss of application documents (possibly accidentally shredded).
Industry
Government & municipal
Listing / capital
Government / public body
Sources
Last updated
October 20, 2026
Card & payment dataHow severity is assessed →

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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: Loss & theft(Physical loss of devices and media)

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