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Malware exposes 8.7 million Daiichi Kosho customers
An employee device infection exposed customer and staff data.
- Organisation
- Nippon Columbia / Daiichi Kosho
- Disclosed
- 11 October 2026
- Affected
- 8,720,000
- Data
- Names, DOBs, emails, phones
- Attacker
- Unknown
- Severity
- critical
- Region
- Global
- Source
- CM Alliance monthly roundup ↗
Cite this
Nuffield Consulting, “Malware exposes 8.7 million Daiichi Kosho customers”, The Daily Tech Wire outage & breach log, 11 Oct 2026. https://techwire.nuffieldconsulting.com/incidents/2026-10-11-nippon-columbia-daiichi-kosho-breach/ (retrieved 15 Nov 2026).
This entry summarises public reporting. Please also cite the original source: CM Alliance monthly roundup, https://www.cm-alliance.com/cybersecurity-blog/biggest-cyber-attacks-data-breaches-ransomware-attacks-october-2026.
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