The health system said the breach occurred due to vulnerabilities in the MOVEit file transfer software that it uses.
The health system learned of the breach June 2. The breach did not affect patient care or operations, according to Harris Health System.
Harris Health System did not disclose how many patients and employees were affected.
Baltimore-based Johns Hopkins University and Health System were also affected by the breach on MOVEit, in addition to several U.S. government networks.
