Ascension Health Data Breach History
WebsiteAscension Health — organization listed in California Attorney General data breach notifications.
This page shows all data breaches of Ascension Health. View the complete breach timeline, records exposed, root causes, and AI breach risk score. BreachHistory tracks disclosed data breaches worldwide.
Data Breach Timeline — All Ascension Health Breaches
- 2025 2025 Ascension Health — California AG data breach notification Unknown records Share
- 2024 2024 Ascension — 437K patients via former partner Cleo file-transfer zero-day 437.3K records Share
- 2024 2024 Ascension — Black Basta ransomware; 5.6M patients and employees 5.6M records Share
Ascension Health Data Breach Summary
This page tracks the Ascension Health data breach history and cybersecurity incidents affecting Ascension Health (United States). BreachHistory currently indexes 3 publicly disclosed or catalogued incidents spanning 2024 through 2025, with approximately 6.0 million records reported as exposed across all indexed events. These totals may include overlapping datasets or third-party estimates and should not be interpreted as unique affected users.
The Ascension Health breach timeline includes major data breaches, cyber attacks, data leaks, credential exposures, API abuse, and other security incidents. Each incident provides details on the estimated records exposed, attack method, affected data types, and supporting public sources. Currently, 0 incidents are company-confirmed.
Largest Ascension Health Data Breaches
The largest indexed incidents include the 2024 Ascension — Black Basta ransomware; 5.6M patients and employees and the 2024 Ascension — 437K patients via former partner Cleo file-transfer zero-day. Record counts originating from threat actors or leak sites should be treated as estimates unless confirmed by Ascension Health or a regulator. Below is the list of large data breaches:
- 2024 2024 Ascension — Black Basta ransomware; 5.6M patients and employees — about 5.6M records exposed · Catalogued incident
- 2024 2024 Ascension — 437K patients via former partner Cleo file-transfer zero-day — about 437.3K records exposed · Catalogued incident
What Information Was Exposed?
Depending on the incident, exposed data may include email addresses, Social Security numbers and national IDs, phone numbers, names, physical addresses, health and medical (PHI) records, and other personal information (PII). The exact data varies between incidents, so review each breach page before assuming your information was affected.
Ascension Health Data Breach 2026
At the time of this update, no Ascension Health data breach has been catalogued for 2026. New incidents are added as official disclosures, regulatory filings, or credible cybersecurity reports become available.
What To Do If You Were Affected
If you believe your account may have been involved in a Ascension Health data breach, change any reused passwords, enable multi-factor authentication (MFA), monitor your account for suspicious activity, and be cautious of phishing emails or fake breach notifications.
This Ascension Health breach history is maintained by BreachHistory using public disclosures, regulatory filings, security research, and clearly labelled third-party claims. For the complete breach timeline, records exposed, incident details, and AI Breach Risk Score, explore the sections on this page.