株式会社ジュンData breach / unauthorized access incident
- Occurred on
- Unconfirmed
- Announced on
- October 8, 2026
- Severity
- BIncidents centered on names and contact details.
- Scale
- Unknown
- Main impact
- A cyberattack occurred in the IDCフロンティア cloud environment used by a contractor, so ジュン announced it would suspend email newsletter distribution. Whether any data was leaked or the scope of impact is unknown.
- Information involved
- Email address
- Cause / key point
- The cause is under investigation.About Supply chain attacks (via vendors & shared services)
- Industry
- Retail & e-commerce
- Listing / capital
- Unlisted
- Last updated
- October 20, 2026
Is this incident worth paying attention to?
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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 →