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Osaka says over 1M email addresses exposed via hacked mail vendor
The breach of the Arara email service used by the city's platform provider exposed addresses of people emailed by the city's system between July and October.
- Organisation
- City of Osaka
- Disclosed
- 13 November 2026
- Affected
- 1,000,000
- Data
- Email addresses
- Attacker
- Unknown
- Severity
- major
- Region
- Global
- Source
- The Record ↗
Cite this
Nuffield Consulting, “Osaka says over 1M email addresses exposed via hacked mail vendor”, The Daily Tech Wire outage & breach log, 13 Nov 2026. https://techwire.nuffieldconsulting.com/incidents/2026-11-13-city-of-osaka-breach/ (retrieved 15 Nov 2026).
This entry summarises public reporting. Please also cite the original source: The Record, https://therecord.media/city-of-osaka-japan-email-data-breach.
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