Reported by 2 outlets

Timeline

1. original reporting

   PEAR Ransomware Group Claims MCBS Data Breach Affecting 1.2 Million Individuals

   securityweek.com · 79d ago · July 27th, 2026

   Atlanta-based medical business management company MCBS (Medical Computer Business Services) disclosed a data breach from September 2025 impacting 1,261,464 individuals. The PEAR ransomware group took credit, claiming to have stolen over 3 TB of files including patient PII/PHI, SSNs, financial documents, and emails. The group has made stolen data available for download on its leak site.

   Seven healthcare organizations whose data was routed through MCBS were named in the notification. PEAR ransomware, which emerged in mid-2025, currently lists over 100 alleged victims on its leak site, including the Motility Software Solutions breach (766,000 affected) and the Tri-Century Eye Care breach (200,000 affected).

   Action: Healthcare organizations using MCBS or similar revenue cycle management vendors should verify whether their data was exposed. Monitor for downstream fraud or phishing targeting affected patients.

2. update from bleepingcomputer.com

   MCBS Data Breach Official Count: 1,261,464 Individuals — PEAR Ransomware Claims Responsibility

   bleepingcomputer.com · 78d ago · July 28th, 2026

   Previously covered Jul 27 (1.2M, PEAR ransomware claim). New today: BleepingComputer reports the official HHs disclosure with confirmed count and specific covered entities named.

   Atlanta-based Medical Computer Business Services (MCBS) has officially disclosed that the September 2025 network breach impacted 1,261,464 individuals in a filing with the U.S. Department of Health and Human Services. Exposed data varies per individual and includes: full name, SSN, DOB, address, health plan beneficiary numbers, health insurance policy numbers, medical history, treatment information, and diagnosis data. MCBS processes patient records for healthcare providers as a billing and practice-management intermediary.