An estimated 5.6 million people had personal information leaked during a May cyberattack against health care provider Ascension, according to the organization. That makes the incident the third-largest breach of health care data reported in 2024.

More than seven months after a ransomware attack disrupted clinical operations at hospitals across the U.S., Ascension submitted a report showing the scope of the cybercrime. The report to federal regulators showed about 5.

The company that runs Manhattan’s Via Christi hospital has told federal regulators that a cyber attack on their systems impacted about five-point-six million people. In the report, Ascension leadership says it continues to work with third-party experts to look further into the personal data that may have been compromised.