Disclosure context

About Sarcoma

Sarcoma is a relatively new ransomware group that emerged in October 2024, operating with apparent financial motivations and demonstrating a broad international targeting approach with at least 140 documented victims across multiple countries and industry sectors. The group's origin and affiliations remain unclear due to its recent emergence, with no publicly documented connections to established ransomware families or confirmation of whether they operate as an independent entity or through a Ransomware-as-a-Service model. Limited public information is available regarding Sarcoma's specific attack methodologies, initial access vectors, or technical capabilities, though their targeting patterns suggest opportunistic rather than highly selective victim selection across diverse industries including manufacturing, business services, agriculture and food production, and technology sectors. The group has shown a particular focus on victims in the United States while also maintaining operations against targets in Italy, Canada, Germany, and Australia, though no specific high-profile attacks or record ransom demands have been publicly documented by major security firms or law enforcement agencies. Given the group's recent emergence in late 2024, Sarcoma appears to remain active with no reported law enforcement disruptions or confirmed rebranding activities at this time. The group has been linked to 150 public disclosures across our corpus. First observed on a leak site on October 9, 2024; most recent post May 12, 2026. The operation is currently active.

Also tracked as: Sarcoma Ransomware Group.

Timeline of this disclosure

October 15, 2025Unimed do Brasil listed by Sarcomaon the group's public leak site

Data size: 2.8 TB

Sector and geography

This disclosure adds to ransomware activity in the Healthcare sector, which has 1,779 disclosures indexed across all operators we track. Geographically, Unimed do Brasil is reported in Brazil, a country with 319 ransomware disclosures in our corpus.

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.

Ransomware victim disclosure

← All victims

Unimed do Brasil

Claimed by Sarcoma · listed 7 months ago

2.8 TB

Data size

Age

since listed · data leaked

Status timeline

Listed
Oct 15, 2025
Data leaked

At a glance

Group: Sarcoma
Status: Data leaked
Country: Brazil
Sector: Healthcare
Listed on leak site: Oct 15, 2025
Data size: 2.8 TB

About the victim

AI dossier — public-source company profile

Unimed Pelotas is a cooperative health service organization located in Pelotas, Brazil, providing a wide range of medical services and health insurance products. They offer digital tools including a mobile application, doctor search guide, and online medical consultations for adults and children. The organization also runs community health and sustainability programs.

Industry: Health Insurance & Medical Services
Address: Pelotas, Brazil

Attack summary

Severity: critical — 2.8 TB of data exfiltrated and published from a healthcare/health insurance cooperative, almost certainly containing regulated medical and personal health information (PHI/PII) at scale, meeting the threshold for critical severity.

The Sarcoma ransomware group claims to have exfiltrated 2.8 TB of data from Unimed do Brasil (Unimed Pelotas) and has published the data, indicating confirmed exfiltration with the archive now disclosed.

critical

Data the group says was taken

AI dossier — extracted from the leak post

Patient health records
Health insurance member data
Personal identifying information (PII)
Medical consultation records
Organizational/administrative files

What the group claims

Unimed do Brasil Unimed Pelotas is a comprehensive health service center located in Pelotas, Brazil, providing a wide range of medical services and assistance. They offer client-friendly features such as an application for convenience, a doctor search guide, and online medical consultations for both adults and children. The organization also emphasizes community involvement through various programs, including health and sustainability initiatives. Their target audience includes individuals seeking health insurance and medical services tailored to their needs.Geo: Brazil - Leak size: 2,8 TB Archive - Contains: Files,SQL

The leak post

captured from the group's site

Site: https://gyf.com.ar/ Industry: Business Services GEO: Argentina 
Site: www.propanelevac.ca Industry: Gas Stations, Retail GEO: Canada 
Site: www.mecmatica.it Industry: Provider of software solutions GEO: Italy 
Site: bedachungen-soellner.de Industry: Commercial & Residential Construction GEO: Germany 
Site: charterindustrial.com Industry: Industrial Machinery & Equipment GEO: USA 
Site: msbuilders.com Industry: Commercial & Residential Construction GEO: USA 
Site: thermofin.de Industry: Building Materials GEO: Germany 
Site: miamimanagement.com Industry: Business Services GEO: USA 
Site: kwg-senftenberg.de Industry: Business Services GEO: Germany 
Site: f1-generation.com Industry: Apparel & Accessories Retail GEO: Germany 
Site: inoxlaghi.com Industry: Industrial Machinery & Equipment GEO: Italy 
Site: maselli.com Industry: Manufacturing innovative optical technology GEO: Italy 
Site: metroheatingandair.com Industry: Commercial & Residential Construction GEO: USA 
Site: hv.com.co Industry: Food & Beverage GEO: Colombia 

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Design and develop IT products and services for the financial market
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Propane Levac inc. specializes in the distribution of propane across Ontari…

Source

Indexed 7 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.