McDonald Building Listed by Sinobi Ransomware Group

On October 17, 2025, the sinobi Ransomware Group listed McDonald Building Co. on its leak site, claiming that internal files had been exfiltrated during a ransomware attack on the construction firm.

What Public Reporting Shows

Public reporting indicates that McDonald Building Co., a construction company specializing in architecture, engineering, and construction projects, was targeted in a ransomware incident. The group posted details on its dark web leak site, accessible via an onion address, claiming to have obtained internal company files. Available reporting describes the data as internal documents but does not specify the exact volume or the precise number of individuals whose information may be contained within those files. No ransom demand deadline has been publicly detailed in the initial listing.

The attack follows the group’s typical pattern of breaching a target’s network, exfiltrating data, and then threatening to publish it unless payment is made. Industry research from sources such as DoxxScan™ continuous monitoring indicates that construction and engineering firms have increasingly become targets because their networks often hold contracts, employee records, vendor details, and client information that can be leveraged for extortion.

Why This Matters for You and Your Family

When a company like McDonald Building Co. suffers a breach, the information exposed can easily include personal details of employees, subcontractors, clients, and their families. Internal files frequently contain Social Security numbers, addresses, dates of birth, banking information, and correspondence that attackers can use to target ordinary people rather than just the business itself.