日本医科大学武蔵小杉病院Data breach / unauthorized access incident
- Occurred on
- January 29, 2026
- Announced on
- February 27, 2026
- Severity
- AFinancial and HR records — information that easily translates into monetary damage.
- Scale
- 130,000 people
- Main impact
- Approximately 130,000 patients' names, addresses and other basic information were publicly exposed. Leakage of medical-record information has not been confirmed and medical services are continuing.
- Information involved
- Home addressFull nameDate of birth
- Cause / key point
- Unauthorized access exploiting a vulnerability in the VPN device used for medical-equipment maintenance.About Exploitation of vulnerabilities
- Industry
- Healthcare
- Listing / capital
- Non-profit corporation
Private university hospital
- Last updated
- October 20, 2026
Is this incident worth paying attention to?
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Attack method classification: Exploitation of vulnerabilities(Breaking in through holes in software and devices)
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