IDCフロンティア（IDCFクラウド）Data breach / unauthorized access incident
- Occurred on
- October 7, 2026
- Announced on
- October 7, 2026
- Severity
- SSLarge-scale compromise of sensitive data such as payment or identity-verification records affecting millions.
- Scale
- 48 records
- Main impact
- Unauthorized queries of registration information for 48 companies were confirmed on the cloud portal; service disruptions affected 495 companies and municipalities, but it was judged that there was no data leak from virtual servers and no traces of external removal were found.
- Information involved
- Email addressUser / member IDPassword
- Cause / key point
- Ransomware attack by a third party.About Ransomware
- Industry
- IT & telecom
- Listing / capital
- UnlistedParent company: IDホールディングス(東証プライム 4709)
IDCフロンティア is a subsidiary of IDホールディングス.
- Sources
- Last updated
- October 20, 2026
Stock price reaction to the disclosureIDホールディングス・親会社 / 東証プライム 4709
Stock information is reference data based on Yahoo Finance and may be delayed. This site does not solicit or advise investment and does not guarantee the accuracy or completeness of this information. We accept no liability for any investment decision based on it.
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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: Ransomware(Encrypting data and demanding a ransom)
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