Was Sierra Management Group hit by ransomware?

Sierra Management Group was listed by the genesis ransomware operation (United States), and stolen data was published on the group's leak site. Darkfield tracks this disclosure with the original leak post, screenshot and group context.

Who is the genesis ransomware group?

genesis is a ransomware operator tracked by Darkfield. See the full operator dossier for its known victims, sectors targeted, IOCs and leak-site infrastructure.

What data was leaked in the Sierra Management Group breach?

genesis published data attributed to Sierra Management Group. Darkfield captured the leak post and a screenshot of the listing.

Ransomware victim disclosure

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Sierra Management Group

Claimed by Genesis · listed 3 months ago

Age

since listed · data leaked

Status timeline

ListedMar 7, 2026
Data leakeddate unknown

At a glance

Group: Genesis
Status: Data leaked
Country: United States
Listed on leak site: Mar 7, 2026

About the victim

AI dossier — public-source company profile

Sierra Management Group, Inc. (SMG) is a Medical Management Services Organization (MSO) based in the United States that provides administrative and management support to independent physicians and physician groups across multiple specialties and locations. Their services include revenue cycle management, billing and coding, contract management, credentialing, surgery scheduling, and comprehensive practice management. The company has been operating for approximately 10 years, supporting urgent care and specialty offices.

Industry: Healthcare Management Services Organization (MSO)

Attack summary

Severity: critical — Sierra Management Group is an MSO serving multiple physician groups and handles regulated healthcare data including medical billing/coding, credentialing, patient scheduling, and financial records across numerous independent medical practices, creating a high likelihood that protected health information (PHI) and PII at scale are involved in the disclosed exfiltration.

The Genesis ransomware group claims to have attacked Sierra Management Group and lists the victim under a 'data_published' status, indicating exfiltration and publication of data. No specific ransom demand or data size was stated in the post.

critical

Data the group says was taken

AI dossier — extracted from the leak post

Physician practice management records
Medical billing and coding data
Patient scheduling information
Credentialing records
Contract management documents
Revenue cycle management data
Employee/staff records
Financial and administrative records

What the group claims

Provides comprehensive medical practice management

The leak post

captured from the group's site

GENESIS GENESIS Archive Tags About GENESIS [email protected] Pequod Associates A global leader in the provision of Marine Claims TPA and Recovery services. 2026-05-11 · 1min Pequod Associates HostBooks (HOT!) An accounting software provider. 2026-05-09 · 1min HostBooks (HOT!) Palo Architecture and Planning. 2026-05-09 · 1min Palo Ben F. Barcus and associates pllc A law firm from Tacoma, WA. 2026-05-09 · 1min Ben F. Barcus and associates pllc Rain Makers Solutions Conducting training sessions, engaging with stakeholders, and organizing meetings and events. 2026-05-08 · 1min Rain Makers Solutions Van Atta Engineering A civil engineering and surveying firm located at 570 Congress Park Dr, Dayton, Ohio. 2026-05-08 · 1min Van Atta Engineering Prescott & Holden A legal firm dedicated to safeguard the rights of its clients 2026-05-08 · 1min Prescott & Holden The American Board of Preventive Medicine A healthcare certification organization. 2026-05-08 · 1min The American Board of Preventive Medicine Integrated Process Engineers & Constructors. Specializes in custom modular process systems, offering a wide range of products including bioreactors, filtration systems, and utility sta…

Sources

Victim sitesierramanagementgroup.com
Leak posthttp://genesis6ixpb5mcy4kudybtw5op2wqlrkocfogbnenz3c647ibqixiad.onion/0fc724d1b71a64ccedc/

Source

Indexed 3 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 genesis

Genesis is a recently emerged ransomware group that was first observed in October 2025, operating with apparent financial motivations based on their targeting patterns across multiple high-value sectors. The group has demonstrated a relatively aggressive operational tempo since emergence, accumulating 54 documented victims within a short timeframe. Given the limited public documentation available from established threat intelligence sources regarding this newly identified group, specific details about their country of origin, organizational structure, and precise attack methodologies remain under investigation by security researchers. The group's targeting patterns indicate a preference for victims in the United States and United Kingdom, with additional activity observed in Malaysia and Spain, suggesting either a broad operational scope or the use of automated targeting tools that do not discriminate by geography. Their sector targeting reveals a focus on healthcare, manufacturing, business services, and financial services organizations, indicating they may prioritize entities with both high revenue potential and critical operational dependencies that increase pressure for ransom payment. Due to the group's recent emergence and limited reporting from major threat intelligence organizations such as Mandiant, CISA, or FBI, comprehensive details regarding their specific encryption methods, initial access vectors, data exfiltration practices, or notable high-profile campaigns have not yet been publicly documented. Genesis remains an active threat as of current reporting, though their operational longevity and potential connections to established ransomware ecosystems continue to be assessed by the cybersecurity community. The group has been linked to 95 public disclosures across our corpus. First observed on a leak site on October 21, 2025; most recent post June 6, 2026. The operation is currently active.

Timeline of this disclosure

March 7, 2026Sierra Management Group listed by genesison the group's public leak site

Other recent disclosures by genesis

genesis has been linked to 95 public victims on Darkfield. A sample of the most recent:

See the full genesis dossier →

Sector and geography

Geographically, Sierra Management Group is reported in United States, a country with 7,392 ransomware disclosures in our corpus.

If your organisation is affected

A listing by genesis means Sierra Management Group 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.
Monitor for the data appearing on genesis'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.