A data breach suffered last year by Atlanta-based medical business management company MCBS (Medical Computer Business Services) affects more than 1.2 million individuals.
According to a data breach notification posted on its website, MCBS was targeted by hackers in September 2025.
An investigation showed that attackers had access to its systems between September 22 and September 26, potentially stealing files that contained personal information such as name, address, SSN, date of birth, health insurance information, and medical information.
The medical revenue cycle management and billing company’s data breach notification names seven healthcare organizations whose data was compromised in this cyberattack.
The healthcare data breach tracker maintained by the US Department of Health and Human Services shows that the MCBS hack impacts 1,261,464 individuals.
The PEAR ransomware group took credit for hacking MCBS in late September 2025, claiming to have stolen more than 3 TB worth of files, including company and client financials, HR and business operations documents, partner and vendor data, patient PII and PHI records, payment details, and emails.
The hackers have made available for download the information allegedly stolen from the company.
The PEAR ransomware group emerged in mid-2025, and its leak website currently lists more than 100 alleged victims.
The cybercrime gang has also taken credit for the Motility Software Solutions hack, which affected 766,000 people, and the Tri-Century Eye Care breach, which affected 200,000 people.
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