Skip to main content
Darkfield

Ransomware victim disclosure

← All victims

McMunn & Yates Building Supplies

listed as McMunn & Yates Building Suppliesorp · Claimed by Sarcoma · listed 2 years ago

21m
Age
since listed · data leaked

Status timeline

  1. ListedOct 15, 2024
  2. Data leakeddate unknown

At a glance

Group
Sarcoma
Status
Data leaked
Country
Canada
Sector
Business Services
Listed on leak site
Oct 15, 2024

About the victim

AI dossier — public-source company profile

McMunn & Yates is a family-owned building supplies retailer and manufacturer founded in 1971 in Dauphin, Manitoba. The company operates multiple divisions including retail building supplies stores, a Commercial Division serving contractors, TIM-BR-FAB Industries (roof and floor truss manufacturing), a Post Frame Division, and a Concrete Division. They serve customers across Manitoba, Saskatchewan, and Northwestern Ontario.

Industry
Building Materials & Supplies Retail; Wood Products Manufacturing
Address
Multiple locations in Manitoba, Saskatchewan, and Ontario, Canada; headquarters/first store in Dauphin, MB
Employees
200-500
Founded
1971

Attack summary

Severity: medium — Data confirmed as published by threat actor, but specific data types, volume, and sensitivity level are not detailed in the available post excerpt. No operational disruption claimed. The company appears to be a B2B supplier rather than holding large volumes of regulated personal data, though contractor and customer records may be at risk.

The Sarcoma group claims to have compromised McMunn & Yates and published exfiltrated data. The group has disclosed the attack on their leak site with data published status confirmed.

medium

Data the group says was taken

AI dossier — extracted from the leak post
  • Business operations data
  • Potentially customer/contractor information
  • Commercial division records

What the group claims

McMunn & Yates Building Supplies It is a story about family first and foremost, of two families coming together. McMunn & Yates was formed in 1971 when Terry Yates and Stan and Gordon McMunn opened their first store in Dauphin, MB. With combined experience in both contract work and retail, this union of families put their faith in each other to build and rebuild something larger than themselves, now hundreds of families serving their local communities large and small. McMunn & Yates is committed to and believe in the hometown values and doing business with their friends and neighbors. We believe the "and" in McMunn & Yates is more than just a conjunction because without it, there are no connections and no commitment. We believe its this commitment to building strong, honest relationships that is the foundation upon which McMunn & Yates rests. McMunn & Yates Commercial Division is a major supplier to builders and contractors. Our Contractor Division delivers with a dedicated team that handles phone-in orders in an efficient and timely manner and provide enhanced contractor services. TIM-BR-FAB Industries is a manufacturer of roof and floor trusses and supplier of pre-engineered wood products serving Manitoba, Saskatchewan and Northwestern Ontario with quality products from its two manufacturing plants located in Dauphin, MB and Oak Bluff, MB. Tim-Br-Fab has a wide selection of manufactured truss systems to choose from or you can work with our specialized design team to build what is right for you. Our cost effective designs are tailored to meet our customers needs and we offer the most durable roof and floor components available today. McMunn & Yates Post Frame Division manufacturers post-frame buildings. Available in fully customized range of styles and sizes, McMunn & Yates Post Frame Division delivers the strongest posts, industry-wide. Steinbach Concrete Division  provides reliable service and quality Redi Mix concrete at competitive prices to Steinbach and su

Sources

Source

Indexed 2 years 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.

Is this your supplier? Your competitor? You?

Pro plans monitor your domain, corporate emails, and crypto wallets across every new ransomware leak-site post, breach dump and Telegram callout — alerts within 5 minutes.

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, 2024McMunn & Yates Building Suppliesorp listed by Sarcomaon the group's public leak site

Other recent disclosures by Sarcoma

Sarcoma has been linked to 150 public victims on Darkfield. A sample of the most recent:

See the full Sarcoma dossier →

Sector and geography

This disclosure adds to ransomware activity in the Business Services sector, which has 3,796 disclosures indexed across all operators we track. Geographically, McMunn & Yates Building Suppliesorp is reported in Canada, a country with 1,055 ransomware disclosures in our corpus.

If your organisation is affected

A listing by Sarcoma means McMunn & Yates Building Suppliesorp 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, CCCS (Canada), as required for your jurisdiction.
  • Monitor for the data appearing on Sarcoma'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.