Cluster · 4 affected providers Kazu Data posted

Doctor Alliance Vendor Breach — Home-Health Cluster

Unauthorized access to the Doctor Alliance physician-certification web portal between October 31 and November 17, 2025. Threat actor "Kazu" exfiltrated ~1.24M files / 353 GB and demanded $200K ransom. Doctor Alliance notified downstream covered entities in January 2026; affected home-health agencies filed their own HHS OCR reports.

Affected

28,230

Providers

4

Window

January–March 2026 (downstream filings)

Threat actor

Kazu