CMF listed on sinobi leak site with claims of data exfiltration

• Ransomware group: sinobi
• Country: United States
• Sector: Manufacturing
• Announcement date: October 12, 2025

The threat actor group known as sinobi has listed CMF on their leak site, claiming to have exfiltrated 140 GB of data. This announcement, made on October 12, 2025, follows a pattern often seen in modern cyberattacks where threat actors use public platforms to pressure organizations by threatening the release of stolen information.

The alleged attack and claims by sinobi

On October 12, 2025, the sinobi group listed CMF on their leak site. The threat actor claims to have gained access to the organization's systems and exfiltrated various data sets. This type of activity is characteristic of double extortion tactics, a method where attackers not only encrypt an organization's data to disrupt operations but also steal sensitive information to use as leverage during ransom negotiations.

The announcement specifies that the compromised information purportedly includes various sensitive datasets. According to the information provided by the threat actor, the breach involves a significant volume of data, with a provided screenshot indicating a total data volume of 140 GB. While the specific file count was not provided in the announcement, the scale of the exfiltration suggests a substantial breach of the organization's digital environment.

Data types involved in the breach

The announcement specifies the types of information that the sinobi group claims to have stolen. According to the leak site post, the stolen data includes several categories of sensitive information that could impact both the company and its associates. The data purportedly includes:

• Financial data
• Contracts
• Customer data

The inclusion of these specific data types highlights the potential impact of the breach on the organization's internal operations and its external relationships.

About CMF

CMF Inc specializes in the design, fabrication, and installation of architectural sheet metal and related products. Since 1956, they have provided metal roofing and siding solutions for commercial, educational, and public projects.

Risk assessment and industry implications

This alleged breach may pose a significant risk of exposure for sensitive corporate and customer information held by CMF. Given that the organization is based in the US, data privacy obligations under relevant state laws and federal regulations may be triggered. The potential compromise of customer data could expose clients and business partners to secondary risks such as identity theft or targeted phishing campaigns.

Furthermore, the publication of contracts might negatively impact the organization's commercial reputation and competitive standing. When contractual terms are made public, it can undermine the strategic advantage of a company and damage the trust established with business partners. In the manufacturing and construction supply sectors, maintaining the confidentiality of project details and pricing is often vital for competitive integrity.

Information regarding the sinobi group is limited; therefore, a definitive assessment of their operational methods and motivations cannot be provided. Organizations facing similar threats often focus on robust defensive measures, such as implementing multi-factor authentication, maintaining offline backups, and conducting regular security awareness training to mitigate the risk of initial access and subsequent data exfiltration.