Shinagawa City security incident history
Hacking, data breaches and other security incidents involving Shinagawa City, with related coverage.
Incidents: 1 · Most recent
Shinagawa childcare programme exposes 195 email addresses in subcontractor breach
↳ Knock-on damage from another organisation’s incident · View original incident195Impact: 195 email addresses leaked
Users' email addresses were leaked following unauthorised access, confirmed on 28 October 2026, at arara, the email delivery subcontractor for School Mail, which is used by Shinagawa City's morning childcare programme. The city said that, as of 5 pm on 10 November, 195 email addresses had been exposed, affecting users who registered with or logged in to School Mail between 30 June and 28 October. Only email addresses were leaked, and there was no unauthorised access to School Mail itself.
Read on www.city.shinagawa.tokyo.jp ↗