← El Camino Health

2026 El Camino Health: Microsoft 365 breach; SSNs, PHI and some bank data

2026 Unknown records affected Share on X

Data compromised

Varies by person: names, contact details, demographics, Social Security numbers, driver licence numbers, dates of birth, medical record and patient account numbers, diagnoses, treatment, prescriptions, provider names, dates of service and health insurance details. For some patients, financial account and routing numbers. The number of people affected has not been published. Call centre: 888-517-6420.

Technical writeup

Source: El Camino Health substitute notice for the 30 October 2026 mailing, with coverage from HIPAA Journal (4 November) and Becker's Hospital Review (about 7 November). No patient count has been released.

Root cause

El Camino Health found unusual activity in Microsoft 365 on 1 September 2026. Four employee accounts were accessed on and off from 26 August to 2 September, and some documents were copied or downloaded. The health system brought in forensic specialists and notified law enforcement. The electronic health record was not involved. How the attacker got in has not been published. Letters started on 30 October 2026, and the review of the remaining documents continues.

References

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