NTT DOCOMO Says Up to About 300,000 Customer Records Leaked

NTT DOCOMO says unauthorized access to Online Shop and My docomo leaked some customer information, with a stated maximum of about 300,000 records.

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NTT DOCOMO Says Up to About 300,000 Customer Records Leaked12

NTT DOCOMO says unauthorized access to DOCOMO Online Shop and My docomo resulted in some customer information leaking.12 The company gives a maximum of about 300,000 records, not a final count.1

SECURITY NOTICE • Reporting cutoff: November 6, 2026, 12:42 AM EST / 2026-11-06T05:42:57Z

The bottom line

DOCOMO says names, addresses, dates of birth, mobile numbers and contact telephone numbers were among the leaked fields.1 The full field set, exact count, cause and intrusion path remained under investigation at the reporting cutoff.1

Verified facts

Maximum scopeUp to about 300,000 records, according to DOCOMO.12
Named data fieldsNames, addresses, dates of birth, mobile numbers and contact telephone numbers.1
Services affectedDOCOMO Online Shop and My docomo.12

What happened

DOCOMO says it detected unauthorized external access on November 4 and stopped procedures in both services at about 1:05 a.m. Japan Standard Time on November 5.1 Its investigation then confirmed that some customer information had leaked.1

Why it matters

Practical analysis: The named fields can make impersonation attempts look more convincing.1 DOCOMO specifically warns that leaked information could be abused in suspicious email, SMS or phone contact impersonating DOCOMO or related parties.1

Current service status

At the notice’s November 5, 6:30 p.m. Japan Standard Time update, emergency maintenance was continuing and restoration timing was undecided.12 DOCOMO said it had observed no new leakage after access was blocked; that is the company’s point-in-time statement, not proof that the incident’s final scope is known.1

What this means for readers

Florida relevance: Direct local exposure appears limited unless a reader uses DOCOMO services or supports someone who does; DOCOMO’s notice does not identify a Florida cohort.1

  • Do not follow links in unexpected messages: DOCOMO tells customers not to access URLs included in suspicious messages.1
  • Do not open unexpected attachments: DOCOMO tells customers not to open attached files.1
  • Do not submit sensitive details: DOCOMO tells customers not to enter or provide personal information, passwords or credit-card information in response to such contact.1

What remains unknown

Scope and cause: The exact record count, complete field set, cause and intrusion path remained under investigation at the cutoff.1

Restoration: The reviewed notice gave no restoration estimate.12

Sources

  1. NTT DOCOMO: customer-information leak notice, second report — November 5, 2026, through 6:30 p.m. JST.
  2. Impress Watch: DOCOMO unauthorized-access report — November 5, 2026.

Update and correction note: This report is bounded to the cited sources and reporting cutoff; unresolved facts are labeled rather than estimated.