Unlimited Technology Systems has disclosed to HHS that a ransomware attack reported in July compromised the data of 3.8 million patients.
The breach traces to an Oct. 5-10, 2025, intrusion into a commercial data center hosting Unlimited Systems’ g4-Centricity for Vector platform. The vendor said it suspended access to the hosted systems, launched a forensic investigation and notified law enforcement.
“Our team conducted a thorough review of the data involved in the incident and has directly notified all Unlimited Systems customers whose data was believed to be involved,” a company spokesperson told Becker’s in July, adding the firm has no evidence the data has been misused.
Unlimited Systems reported the number of affected individuals to HHS’ Office for Civil Rights on July 21, while the agency posted the figure in August.
Exposed data may include Social Security numbers, medical record numbers, diagnosis details and scanned identification documents, though the company said full medical records, imaging and financial account numbers were not involved.
As a business associate serving specialty healthcare practices nationwide, Unlimited Systems now ranks among the largest health data breaches reported to HHS this year, underscoring yet again how a single vendor incident can multiply across patients who have no direct relationship with the company.
