Novocure data breach affects more than 1,400 cancer patients

In mid-August 2026, Novocure experienced unauthorized access to some of its information systems, resulting in exposure of data for over 1,400 U.S. cancer patients and an undisclosed number of employees. Most patient records accessed contained only ID numbers without names or other identifiers, but fewer than 50 patients had identifying and healthcare provider contact information exposed. Employee contact information including job titles and phone numbers was also compromised. The company confirmed no access to medical treatment devices or operational disruption occurred. The ShinyHunters extortion group claimed responsibility and leaked a 33GB archive of stolen files. Novocure is assessing legal and regulatory notification obligations. The breach adds to a recent pattern of healthcare sector cyberattacks involving ShinyHunters.

The breach exposed sensitive patient data including ID numbers for over 1,400 U.S. cancer patients, with identifying and healthcare provider contact information for fewer than 50 patients. Employee contact information was also compromised. There was no impact on medical treatment devices or company operations. The exposure of patient and employee data could lead to privacy risks and regulatory consequences. The public leak of stolen data by the ShinyHunters extortion group increases the risk of further misuse of the information.

Novocure is currently evaluating regulatory and legal notification requirements and will notify impacted patients as required. No information is available on how the breach occurred or if a ransom was paid. Organizations should monitor official communications from Novocure for updates. Since no patch or fix applies to this breach, mitigation focuses on incident response, notification, and strengthening access controls to prevent unauthorized access. No immediate remediation actions are specified by the vendor.