Cornerstone Care Center Data Breach Exposes SSNs and Medical Records

Cornerstone Care Center, a skilled nursing and long-term care facility in Sanger, California, disclosed a data breach involving unauthorized access to protected health information. The total number of individuals affected has not been publicly disclosed.

On or around April 7, 2026, Cornerstone Care Center became aware of unauthorized activity involving one user account, according to the company's notification. Upon discovery, the facility took steps to contain the incident. A third-party forensic firm was brought in to investigate.

Nine days later, on April 16, 2026, Cornerstone Care Center completed its investigation and determined that a limited amount of protected health information kept in the normal course of business may have been accessed by an unauthorized third party.

The types of information exposed included full name, date of birth, date of service, health insurance information, lab results, medical diagnosis information, medical record number, patient identification number, prescription and treatment information, provider name and Social Security number.

Cornerstone Care Center began notifying affected individuals on May 1, 2026. The company posted a notice on its website and notified the attorney general of California.

Cornerstone Care Center's response to the breach

Cornerstone Care Center has set up a toll-free call center to answer questions about the incident and address related concerns. The call center is available from 8 a.m. to 8 p.m. Eastern time, Monday through Friday, excluding holidays.

Affected individuals can reach the call center at 833-289-1066. Individuals may also contact the company by email at cyberincident@jerichocare.com or by writing to 2550 9th St., Sanger, CA 93657.

The company is additionally offering an online credit monitoring service for 12 months provided by Cyberscout, a TransUnion company, to affected individuals.

Steps to take if your information was exposed

• Place a fraud alert or credit freeze on credit reports by contacting Equifax at 1-888-298-0045, Experian at 1-888-397-3742 and TransUnion at 1-800-680-7289, as the exposure of Social Security numbers increases the risk of identity theft.
• Request free credit reports at AnnualCreditReport.com and review them carefully for unfamiliar accounts or unauthorized inquiries.
• Monitor Explanation of Benefits statements from health insurers for medical services, prescriptions or claims that were not authorized, since medical information was included in this breach.
• Watch for phishing attempts that reference Cornerstone Care Center or this data breach by name, as scammers often use breach notification details to craft convincing emails, texts or phone calls.
• Report any suspected identity theft to local law enforcement, the state Attorney General or the Federal Trade Commission at identitytheft.gov or 1-877-438-4338.
• California residents can contact the Office of Privacy Protection at oag.ca.gov/privacy or the Attorney General of California at 1-800-952-5225 for additional guidance on protection against identity theft.