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