Mainline Health Systems data breach impacted over 100,000 individuals

Mainline Health Systems disclosed a data breach that impacted over 100,000 individuals.

Mainline Health Systems is a nonprofit Federally Qualified Health Center founded in 1978 in Portland, Arkansas, serving Southeast Arkansas . With over 30 locations across multiple counties—including in-school clinics and community centers—it provides comprehensive primary medical, dental, and behavioral health services.

The healthcare organization disclosed a data breach that impacted 101104 individuals. The security incident occurred on or about April 10, 2024, and impacted the company network.

“Upon learning of the issue, we commenced a prompt and thorough investigation. As part of our investigation, we notified federal law enforcement of the incident, engaged external cybersecurity experts and conducted a manual review of the impacted files.” reads the data breach notification letter shared with the Maine Attorney General’s Office. “Based on that review we discovered on May 21, 2025 that certain files containing your protected personal information were subject to unauthorized access or acquisition as a result of the incident

The Inc Ransom group claimed responsibility for the attack and added the organization to its Tor leak site.

The INC RANSOM has been active since 2023, it claimed responsibility for the breach of tens of organizations to date. The list of victims includes National Health Service (NHS) of Scotland and the American multinational corporation Xerox Corp.

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Pierluigi Paganini

(SecurityAffairs – hacking, Mainline Health Systems)