M3: unauthorized access to the MR-kun service for drug makers
On 15 October, M3 said unauthorized access to the system of MR-kun, its service for pharmaceutical companies, leaked personal data of physician members and drug company staff. Fewer than 10% of all physician members and several hundred drug company staff are affected; names, workplaces and, for some, email addresses were included. The exact number is still being checked. Login passwords and m3 points were not included.
Disclosed
2026-10-15
Organizations involved
1
Leaked or at risk
Unknown
Downtime
Unknown
Timeline
- Disclosed 2026-10-15
- 1 days
Attack or cause
- Method
- [Intrusion]
- Impact
- [Data leak]
- Entry point
- Unknown
Data exposed or at risk
Services hit
Organizations involved
[Breached][Major]Tokyo, MinatoInformation and communications
M3, Inc.
Sources
- [1][News]医師の氏名や勤務先などが漏えい エムスリーに不正アクセスASCII.jp · 2026-10-16
- [2][News]エムスリーが個人情報漏洩 製薬向けサービスに不正アクセスNikkei · 2026-10-15