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Healthcare Ransomware Attacks Expose Patient Data at Major Providers

Updated 3mo agoFirst seen Dec 19, 20252 sources

Richmond Behavioral Health Authority (RBHA) and MedStar Health, two major healthcare providers in the Mid-Atlantic region, have disclosed significant ransomware incidents resulting in the exposure of sensitive patient data. RBHA reported that hackers gained unauthorized access to its systems on September 29, 2025, deploying ransomware that encrypted files containing personal and protected health information for up to 113,232 individuals. Although RBHA stated there was no definitive evidence of patient data being accessed, the organization is notifying all potentially affected individuals and has implemented enhanced security measures, including third-party monitoring and stronger data policies.

MedStar Health, which operates hospitals and care sites across Maryland, Virginia, and Washington D.C., confirmed a separate ransomware attack attributed to the Rhysida group, which claims to have exfiltrated 3.7 terabytes of data, including over 7 million pieces of patient information. The breach, occurring between September 12 and 16, 2025, involved the compromise of names, dates of birth, Social Security numbers, and detailed patient care information. MedStar has begun notifying affected patients and is offering complimentary identity monitoring services to those whose most sensitive data was exposed. Both incidents highlight the ongoing threat of ransomware to healthcare organizations and the significant risks to patient privacy and data security.

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Healthcare Ransomware Attacks Expose Patient Data at Major Providers
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EVENT TIMELINE

How this story unfolded

6 events from the most recent confirmed update back to the earliest known activity.

6 EVENTS
Dec 18, 20256mo ago

MedStar Health notifies patients and responds to breach

MedStar Health began notifying affected patients of the breach, secured its systems, engaged third-party investigators, notified law enforcement, and offered identity monitoring. The incident also prompted proposed federal class action litigation alleging negligence.

RBHA discloses breach and begins notifications

RBHA publicly disclosed the breach, said up to 113,232 individuals may be affected, and began notifying impacted people out of caution. The authority also said it engaged third-party cybersecurity experts and implemented additional security measures while the investigation continues.

Qilin claims RBHA attack and publishes stolen data

Qilin claimed responsibility for the RBHA incident, saying it exfiltrated 192 GB of data and published the files on its dark web leak site. The exposed material reportedly included sensitive patient information.

Rhysida offers MedStar Health data for sale

After the MedStar intrusion, the Rhysida ransomware group claimed responsibility and posted the stolen MedStar data for sale on its leak site. The group later made the data publicly accessible, escalating the impact of the breach.

Sep 30, 20259mo ago

RBHA discovers unauthorized access to its systems

Richmond Behavioral Health Authority said it discovered unauthorized access to its systems on September 30, 2025. The incident ultimately led to a breach disclosure affecting up to 113,232 individuals.

Sep 12, 20259mo ago

MedStar Health data theft occurs over four days

MedStar Health said unauthorized access and data theft took place between September 12 and 16, 2025, exposing sensitive patient and medical information. Rhysida later claimed it stole 3.7 TB of data, including more than 7 million pieces of patient information.

LINKED ENTITIES

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Vulnerabilities, threat actors, malware, products, organizations, and breaches Mallory has linked to this story.

5 LINKEDOpen in app
Threat actors
2 linked
Malware
1 linked
Organizations
2 linked
Qilin RansomwareRichmond Behavioral Health Authority
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