SHINDO2

e-Clinic

21st Century Medicine Study Group (NPO)

Unauthorized accessSize not disclosed

POSSIBLE LEAKInvestigating

Open in the live monitor ▶
Disclosed
Jun 24, 2026
Leak
Leak possible
Type
Unauthorized access
Status
Investigating
Security spend
Not checked yet
Compensation
Not announced

What leaked

UnspecifiedPersonal data of newsletter subscribers and others

Not leaked

  • The member management and fee payment systems were not affected

Who is affected

  • Newsletter subscribers

Cause

Outside unauthorized access to the server of Merupai-kun, the external newsletter service used

Timeline

  1. Intrusion began
  2. First disclosure

Response

  • Service stopped

Using another delivery method until Delightful finishes its investigation

What you should do

  1. Check the company's notice to see if you're affected

Lessons for companies

  1. Put security requirements, audit rights and reporting deadlines in vendor contracts
  2. Report to the PPC: preliminary in 3–5 days, final in 30 (60 if malicious)
  3. Run red teaming and AI-assisted hardening, and publish how much you invest

Sources