One Medical Data Breach: ShinyHunters Exfiltrates 8.8 TB of Patient Data
One Medical, an Amazon-owned primary care provider, experienced a cybersecurity incident where an unauthorized third party gained access to a third-party file storage system containing archived information for One Medical Seniors patients. The unauthorized access occurred between June 8 and June 11, 2026. The ShinyHunters threat group claimed responsibility, stating they exfiltrated 8.8 terabytes of data. The compromised data included demographic information and clinical records of Iora Health/One Medical Seniors patients. One Medical confirmed the breach was limited to this legacy data platform.
Signal context
First seen: Jun 11, 2026
Last updated: Jun 29, 2026
Status: Public signal
Key points
- Unauthorized access occurred between June 8 and June 11, 2026.
- Affected a third-party file storage system for One Medical Seniors patients.
- ShinyHunters claimed exfiltration of 8.8 TB of data.
Signal analysis
BetaThis analysis groups the signal by industry, likely incident action and impacted security area. It helps compare this signal with other published signals without treating the labels as final determinations.
Sector: Information
Likely country: Location not provided
The feed marks multiple actor roles. Treat this as a review signal rather than a final attribution.
- Source type: outside the affected organization
- Source type: supplier or third-party involvement
Impact area: Confidentiality
Likely asset: User or customer data
- 26 signals in the same sector
- 90 signals with the same likely impact area
- 1 signal linked to this organization/domain
External sources
One Medical Seniors Data Breach Exposes Patient Information - Claim Depothttps://www.claimdepot.com/data-breach/one-medical-2026Public source from claimdepot.com.
One Medical Under Investigation for Data Breach - Schubert Jonckheer & Kolbehttps://www.classactionlawyers.com/blog/onemedicalPublic source from classactionlawyers.com.
Amazon One Medical Seniors discloses health data breachhttps://www.benefitspro.com/2026/06/22/amazon-one-medical-seniors-discloses-health-data-breach/Public source from benefitspro.com.
One Medical Under Investigation for Data Breach - Schubert Jonckheer & Kolbehttps://www.sjklaw.com/cases/one-medical-data-breach-investigation/Public source from sjklaw.com.
ShinyHunters Data Extortion Group Threatens to Leak 8.8 TB of Stolen One Medical Datahttps://www.hipaajournal.com/one-medical-data-breach/Public source from hipaajournal.com.
SWK Cybersecurity News Recap June 2026https://www.swktech.com/swk-cybersecurity-news-recap-june-2026/Public source from swktech.com.
Data Breach Roundup (June 12 - 18, 2026) - Privacy Guideshttps://www.privacyguides.org/news/2026/06/19/data-breach-roundup-june-12-18-2026/Public source from privacyguides.org.
One Medical Seniors reports data breach of third-party vendor impacting 'limited' number of patients - Fierce Healthcarehttps://www.fiercehealthcare.com/health-tech/one-medical-seniors-reports-data-breach-third-party-file-storage-systemPublic source from fiercehealthcare.com.
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