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Hematology Oncology Consultants

Claimed by Rhysida · listed 9 months ago

9m
Age
since listed · data leaked

Status timeline

  1. ListedOct 17, 2025
  2. Data leakeddate unknown

At a glance

Group
Rhysida
Status
Data leaked
Country
United States
Sector
Healthcare
Listed on leak site
Oct 17, 2025

About the victim

AI dossier — public-source company profile

Hematology Oncology Consultants is a private medical practice based in Michigan that specializes in the treatment of cancer and blood disorders. The practice is dedicated to providing high-quality care in a healing environment addressing the physical and emotional needs of patients. It operates as Michigan Hematology Oncology, serving patients across Michigan.

Industry
Oncology & Hematology Medical Practice

Attack summary

Severity: critical — The victim is a specialist oncology and hematology private practice; data published almost certainly includes highly sensitive regulated medical records (PHI/PII) of cancer and blood disorder patients, constituting a critical HIPAA-covered breach of sensitive health data at scale.

The Rhysida ransomware group claims to have attacked Hematology Oncology Consultants and has published data from the breach. The disclosure is listed as data_published, indicating exfiltration and release of data from this oncology and hematology practice.

critical

Data the group says was taken

AI dossier — extracted from the leak post
  • Patient medical records
  • Cancer and blood disorder treatment data
  • Patient personal identifiable information
  • Practice administrative records

What the group claims

Hematology Oncology Consultants Michigan Hematology Oncology is a private practice dedicated to providing the highest level of quality care in a healing environment for the mind, body and spirit of patients dealing with cancer and blood disorders.

Source

Indexed 9 months ago

This page surfaces a public ransomware disclosure indexed by Darkfield. Original posts come from the operator's own leak site; we cross-check against ransomware.live, RansomLook and RansomWatch where applicable. Share this URL freely.

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Disclosure context

About Rhysida

Rhysida is a ransomware group that emerged in June 2023, operating with primarily financial motivations through targeted attacks against critical infrastructure and public sector organizations. The group's origin and potential state affiliations remain unclear, though they operate independently rather than as a traditional Ransomware-as-a-Service model, with limited public documentation regarding connections to other cybercriminal organizations. Rhysida employs double extortion tactics, typically gaining initial access through compromised VPN credentials and exploiting vulnerable public-facing applications before deploying their ransomware payload and exfiltrating sensitive data prior to encryption. The group has demonstrated a particular focus on healthcare and educational institutions, with notable attacks documented by CISA and FBI advisories highlighting their targeting of hospitals and school districts across multiple countries, resulting in significant operational disruptions to critical services. As of late 2024, Rhysida remains an active threat with continued operations targeting organizations primarily in the United States, Canada, and other Western nations, maintaining their focus on high-value sectors where operational disruption can maximize ransom payment likelihood. The group has been linked to 282 public disclosures across our corpus. First observed on a leak site on June 5, 2023; most recent post June 18, 2026. The operation is currently active.

Timeline of this disclosure

  • October 17, 2025Hematology Oncology Consultants listed by Rhysidaon the group's public leak site

Other recent disclosures by Rhysida

Rhysida has been linked to 282 public victims on Darkfield. A sample of the most recent:

See the full Rhysida dossier →

Sector and geography

This disclosure adds to ransomware activity in the Healthcare sector, which has 2,600 disclosures indexed across all operators we track. Geographically, Hematology Oncology Consultants is reported in United States, a country with 11,033 ransomware disclosures in our corpus.

If your organisation is affected

A listing by Rhysida means Hematology Oncology Consultants appeared on a ransomware extortion site and data attributed to it has been published. If this is your organisation, or a supplier you depend on, the priority is to confirm the intrusion and contain it before the window to act closes.

  • Engage your incident-response team and preserve forensic evidence before remediating — do not wipe affected systems first.
  • Force a password reset and revoke active sessions for exposed accounts; rotate any credentials, API keys or certificates that may have been in the stolen data.
  • Assess regulatory notification duties (GDPR, NIS2, sector regulators) — many carry a 72-hour reporting clock from awareness.
  • Report the incident to your national CERT, CISA (United States), as required for your jurisdiction.
  • Monitor for the data appearing on Rhysida's leak site and across paste and breach channels, and brief downstream partners who may be exposed through you.

How we know this. Darkfield monitors public ransomware leak sites continuously, archiving every new disclosure and the data later released against the victim. Each entry on this page is sourced from the operator's own publication and cross-checked against complementary OSINT feeds (RansomLook, ransomware.live, RansomWatch). We do not collect or host stolen data — only the metadata, timestamps and screenshots needed to make the public disclosure searchable and accountable. Records here are corrected when the original post is edited, retracted, or merged with another disclosure.