sinobi ransomware group lists C.M.G, entreprise de serrurerie et métallerie à Saint Calais on its leak site

• Ransomware group: sinobi
• Country: France
• Sector: Manufacturing
• Announcement date: October 30, 2025

French metalworking firm C.M.G targeted by sinobi ransomware group

The threat actor known as sinobi has listed the French-based organization C.M.G, entreprise de serrurerie et métallerie à Saint Calais, on its dedicated leak platform. According to the announcement made on October 30, 2025, the group claims that the institution's data has been encrypted during the attack.

Details of the claimed attack

The incident involves the sinobi ransomware group, which has published the name of the victim on its leak site. The group's claim, announced on October 30, 2025, asserts that the institution's data has undergone encryption. This type of attack is a common tactic used by ransomware operators to disrupt business operations and pressure victims into paying a ransom.

In many modern ransomware campaigns, threat actors employ a strategy known as double extortion. In these scenarios, attackers do not only encrypt the victim's files to halt operations but also exfiltrate sensitive information beforehand. The threat of leaking this stolen data on a public platform serves as additional leverage to compel the organization to meet the attackers' demands. While the specific mechanics of this particular incident remain under the group's claim, the listing on a leak site is a hallmark of such extortion tactics.

Data involvement and evidence

Regarding the specific information involved in this breach, the available evidence is limited. The screenshots provided by the threat actor display visual evidence of file names and planning documents. However, there is no detailed information regarding the full scope or the specific nature of the leaked data. Furthermore, the group has not provided information regarding the total size of the data or the specific count of files involved.

The listing names no specific data types in a structured format, leaving the full extent of the potential exposure unknown to the public. The lack of detailed information regarding the volume of data or the specific categories of files makes it difficult to assess the complete impact of the breach at this stage.

Risk assessment and organizational implications

This incident may pose a significant risk to the institution's operational continuity and could lead to disruptions in business processes. Because the organization operates in France, a potential data leak might trigger legal obligations and administrative sanctions under the GDPR (General Data Protection Regulation). Organizations operating within the European Union must adhere to strict protocols regarding data protection and the timely notification of authorities and affected individuals following a breach.

Beyond the immediate operational and legal concerns, there are secondary risks to consider. The leaked data, if utilized by malicious actors, could be used for identity theft or targeted phishing attacks against the company or its stakeholders. Such attacks often follow a breach, as attackers use the stolen information to craft highly convincing fraudulent communications.

For organizations in the manufacturing and metalworking sectors, maintaining robust cybersecurity posture is essential. Common defensive steps to mitigate these risks include implementing regular data backups that are stored offline, enforcing multi-factor authentication across all systems, and conducting regular security awareness training for employees. Additionally, organizations should maintain a comprehensive incident response plan and ensure that their data security processes are reviewed and updated frequently to defend against evolving threats. As information about the sinobi group remains limited in the public domain, organizations facing similar threats should remain vigilant and consider notifying relevant authorities to comply with regulatory requirements.