GMOインターネット（お名前.com デスクトップクラウド）Data breach / unauthorized access incident
- Occurred on
- October 20, 2026
- Announced on
- October 21, 2026
- Severity
- SCompromise of deep personal data or usable credentials.
- Scale
- 26,739 records
- Main impact
- On お名前.com デスクトップクラウド, used as VPS for FX automated trading, unauthorized programs were confirmed installed on some customer server environments on 2026-10-20. To prevent spread, from 10-21 4:00 the company sequentially stopped 26,739 servers across all plans (restoration timing undecided); a second report (10-22) found that trading account login information stored on servers may have been obtained and illicitly used, and reports of fraudulent operations on trading accounts since 10-21 are being accepted; the company does not hold payment information including credit cards, is coordinating guidance with related businesses and consulting the Tokyo Metropolitan Police, and is urging customers to change server authentication credentials, change passwords used on other services, and watch for opportunistic phishing.
- Information involved
- Password
- Cause / key point
- Installation of unauthorized programs in customer server environments and unauthorized access by third parties (attack vector under investigation).About Targeted email & phishing
- Industry
- IT & telecom
- Listing / capital
- UnlistedParent company (listed holding company): GMOインターネットグループ株式会社(東証プライム 9449.T)
The primary party, GMOインターネット株式会社, is unlisted; the listed holding company is GMOインターネットグループ株式会社 (9449, TSE Prime).
- Sources
- Last updated
- October 23, 2026
Stock price reaction to the disclosureGMOインターネットグループ株式会社・親会社（上場持株会社） / 東証プライム 9449.T
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.
Where to go for this information
The steps themselves are on the protection guide. These links match the kinds of data in this incident, plus support contacts.
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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: Targeted email & phishing(Fake emails and sites that steal credentials)
Read the Targeted email & phishing guide and national trends →