The personal as well as medical data of around 20 million individuals was leaked on Oracle Health’s legacy Cerner systems in early 2025. Oracle has not disclosed the number of affected persons yet. Cerner an electronic health records (EHR) company merged with Oracle in June 2022. The former was valued at around $28.3 billion.

Oracle started alerting customers in March of last year. The former’s notice read “We are writing to inform you that, on or around February 20, 2025, we became aware of a cybersecurity event involving unauthorized access to some amount of your Cerner data that was on an old legacy server not yet migrated to the Oracle Cloud.”

This is one of the biggest healthcare data breaches reported in the US. The total number has come from regulatory filings and breach notifications related to Cerner. Texas alone is estimated to have around 3 million victims. As per evidence an attacker had utilized stolen customer credentials to get access to the server post January 22 last year. The former then copied data to a remote server.

The breach was discovered on February 20 last year. Hospitals affected by this incident got extortion demands from a person calling himself “Andrew”. The hacker demanded millions of dollars in cryptocurrency. If the payment was not made the stolen data would be leaked or sold. This particular attack is smaller than the 2024 Change Healthcare ransomware attack, which ultimately affected 192.7 million individuals.

SOURCES:-

https://www.securityweek.com/oracle-health-data-breach-tally-climbs-to-nearly-20-million/

https://the420.in/oracle-health-cerner-data-breach-nearly-20-million/

https://www.rescana.com/post/oracle-health-cerner-2026-data-breach-exposes-nearly-20-million-patient-records-across-80-u-s-hospitals

https://finance.yahoo.com/healthcare/articles/oracle-orcl-health-data-breach-191239794.html

https://www.sec-news.ai/news/oracle-health-data-breach-exposes-nearly-20-million-records