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JAENES
APartial leak confirmedOctober 13, 2026 announced

ゴルフダイジェスト・オンライン（GDO）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
October 13, 2026
Announced on
October 13, 2026
Severity
AFinancial and HR records — information that easily translates into monetary damage.
Scale
1,789 records
Main impact
At GDO, a leak of 1,789 records containing names and corporate email addresses of employees, former employees, and contractors was confirmed, and separately 55 member records may have been queried externally, of which 4 include personal information.
Information involved
Email addressPhone numberHome addressFull nameDate of birth
Cause / key point
The cause is under investigation.About Supply chain attacks (via vendors & shared services)
Industry
Retail & e-commerce
Listing / capital
Unlisted
Sources
Last updated
October 20, 2026
Email addressPhone numberHome addressFull nameDate of birthHow 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

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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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