Notice of Cerner’s Data Security Incident
This notice provides information about a recent security incident and data breach at the Cerner Corporation (“Cerner”), the vendor that provides electronic medical record services to many healthcare providers, including AllianceHealth Durant and Madill.
In late February 2025, Cerner learned that an unauthorized third party had gained access to certain Cerner systems as early as January 22, 2025. Cerner investigated the incident, engaged external cybersecurity specialists, initiated its critical incident response process, took steps to secure the impacted systems, and engaged with federal law enforcement.
On October 28, 2025, Cerner told us the unauthorized third party gained access to personal health information that Cerner was maintaining on behalf of AllianceHealth Durant and Madill. This incident did not involve any patient information maintained at [CHS facility] and did not cause any disruption to our electronic medical records or our clinical operations.
Immediately after Cerner notified us of the incident, we began working with Cerner to identify the patients whose information was involved in the incident. The information involved varied by patient, but may include names, Social Security numbers, and information included within patient medical records, such as medical record numbers, doctors, diagnoses, medicines, test results, images, care and treatment.
Letters are being mailed to patients whose information was involved in this incident. For patients whose information was involved, Cerner is offering a complimentary two-year membership to Experian identity protection services. Patients are also encouraged to carefully review statements sent to them from healthcare providers, insurance companies, and financial institutions to ensure that all account activity is valid. Patients should report any questionable charges or inaccurate medical record information promptly to the company that maintains the patient’s accounts or records.
If you have further questions or concerns, please call 833-745-2417 toll-free Monday through Friday from 8 am – 8 pm Central (excluding major U.S. holidays). Please be prepared to provide engagement number B156255.