Skip to content
JAENES
BPossible leakSeptember 9, 2026 announced

鴨川市（ふるさと納税アンケート）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
August 31, 2026
Announced on
September 9, 2026
Severity
BIncidents centered on names and contact details.
Scale
218 people
Main impact
Due to a misconfiguration of a commissioned questionnaire, the names, addresses, and phone numbers of 218 respondents were viewable by other respondents (a follow-up corrected that email was not affected).
Information involved
Phone numberHome addressFull name
Cause / key point
Insufficient verification of the questionnaire system settings.About Supply chain attacks (via vendors & shared services)
Industry
Government & municipal
Listing / capital
Government / public body

City's ふるさと納税 administration

Sources
Last updated
October 20, 2026
Phone numberHome addressFull nameHow severity is assessed →

Is this incident worth paying attention to?

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

Related incidents

Browse the database →

Incidents sharing the same company, service, attack method or industry (grouped automatically from the disclosures).

Same attack method

Same industry

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 →

← Back to Breach Watch