NHKData breach / unauthorized access incident
- Occurred on
- March 17, 2026
- Announced on
- March 18, 2026
- Severity
- CLimited data such as email addresses and identifiers.
- Scale
- 32,940 people
- Main impact
- Due to a business email misdelivery, email addresses of 15,199 NHK employees and staff, 9,188 people from related organizations, and 8,553 external contractors, totaling 32,940 people, were visible to other recipients.
- Information involved
- Email address
- Cause / key point
- An external vendor responsible for IT system maintenance made an operational error, sending group emails in batches of 100 with the recipient list visible to all recipients.About Supply chain attacks (via vendors & shared services)
- Industry
- Media & entertainment
- Listing / capital
- Government / public body
Public broadcaster (NHK)
- Last updated
- October 20, 2026
Is this incident worth paying attention to?
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: 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 →