- State
- IL
- Covered entity type
- Healthcare Provider
- Individuals affected
- 55,983
- Business associate present
- Yes
- Type of breach
- Hacking/IT Incident
- Location of breached information
- Network Server
- First seen by InfoSec Signals
- 9/23/2026
- Last seen in OCR export
- 9/23/2026
OCR description
The covered entity (CE), Northwestern Memorial Healthcare, reported that its business associate (BA) experienced a ransomware attack affecting the electronic protected health information (ePHI) of approximately 55,983 individuals. The ePHI involved included names, addresses, and treatment information. The CE notified HHS, affected individuals, the media, and provided substitute notice.
Change history
- 9/23/2026Added to OCR's archive list
Source: U.S. Department of Health and Human Services, Office for Civil Rights, Breach Portal. Records are reproduced as published; entity names and figures are OCR's.