Expert MRI Suffers Major Data Breach, Exposing Sensitive Patient Information Expert MRI, a California-based diagnostic imaging provider, confirmed a significant data breach after unauthorized actors accessed its network between June 2 and August 24, 2025. The cyberattack, claimed by the threat actor PEAR, involved ransomware deployment and the theft of approximately 617 GB of sensitive data, which was later posted on the dark web on September 6, 2025. The compromised data includes personally identifiable information (PII) and protected health information (PHI), such as names, addresses, dates of birth, medical diagnoses, treatment details, and—in some cases—Social Security numbers. The combination of PII and PHI heightens risks of identity theft and fraud for affected individuals. The breach was detected following an investigation that revealed files were copied from Expert MRI’s network. The company has since engaged third-party cybersecurity experts to assess the incident’s scope and identify impacted individuals. Expert MRI has published a cybersecurity event notice detailing the breach and established a call center (855-720-3740) for affected individuals seeking further information. The incident underscores the growing threat of ransomware attacks targeting healthcare providers and the severe consequences of large-scale data exfiltration.