Data breach
Medstar Health
- Records
- 12,730,153
- Breach date
- 4 October 2025Estimated
- Added
- 21 October 2025
What was exposed
8 types of data · 1 puts you at serious risk
- Names12,730,153
- Dates of birth9,004,114
- Phone numbers6,847,785
- Street addresses6,069,617
- Social security numbers4,672,269
- Email addresses3,172,754
- Home addresses1
- Medical diagnoses1
About this breach
Medstar Health suffered a data breach in October 2025. The leaked dataset holds 12,730,153 records. It was added to this catalogue on 21 October 2025.
What Information Was Compromised?
The records include names, dates of birth, phone numbers, street addresses, social security numbers, email addresses, home addresses and medical diagnoses. Social security numbers can be used for fraud and identity theft.
It is listed as a sensitive breach: an email check does not name it, and counts it among the breaches that are not listed publicly.
What Should You Do If You Were Affected?
Consider a credit freeze or a fraud alert, and watch for accounts or loans opened in your name. Expect scam calls and texts that use your real details. Be wary of emails and messages that mention this breach or ask you to confirm personal details.
There is no public write-up of this breach yet: this summary is written from its record.