Kleven Construction targeted by Hunters ransomware group

• Ransomware group: Hunters
• Country: United States
• Sector: Professional Services
• Announcement date: July 31, 2024

Hunters ransomware group claims attack on Kleven Construction

The threat actor known as Hunters International has listed the United States-based organization Kleven Construction on its dedicated leak site. According to the group's announcement, which was posted on July 31, 2024, the attackers claim to have successfully exfiltrated and encrypted a significant volume of data belonging to the company.

This incident follows a common pattern observed in modern cyberattacks, often referred to as double extortion. In such scenarios, threat actors do not merely encrypt an organization's files to disrupt operations; they also steal sensitive information to use as leverage. By threatening to leak this data on public forums or leak sites, attackers aim to pressure the victim into paying a ransom to prevent the public exposure of confidential information.

Details of the alleged data breach

The claim made by Hunters International suggests a substantial impact on the target's digital assets. The group alleges that they have gained control over 124.5 GB of data, which is comprised of 191,587 individual files. The announcement implies that the organization's operational data may have fallen under the control of these threat actors as a result of the attack.

Based on the information provided through screenshots associated with the leak, the allegedly exfiltrated data includes several sensitive categories of information. These include:

• Accounting records
• Economic activity data
• Investor information
• Management data
• IT system information

The breadth of this data suggests that the attackers may have gained access to core business functions, ranging from financial management to technical infrastructure details.

Organization profile

Kleven Construction is a construction and contracting company based in the United States. The firm operates across various sectors, handling both residential and commercial projects.

Analysis and potential implications

This leak claim may pose a significant risk of exposing the personal data of Kleven Construction employees and stakeholders. Because the organization is located in the United States, a potential data breach could trigger various notification obligations under relevant state laws and federal regulations. The specific nature of the leaked data, which includes management and investor information, may increase the likelihood of it being used for targeted phishing attacks against the organization's supply chain partners.

Regarding the threat actor, Hunters International is known to utilize the Hive ransomware codebase. While reports have indicated that the group may have ceased encryption activities as of 2025, this specific claim highlights the ongoing evolution of their tactics. Such a shift might indicate a change in the group's current strategy or a focus on different stages of the attack lifecycle.

For organizations operating in the professional services and construction sectors, these types of incidents underscore the importance of robust defensive measures. Common defensive steps include maintaining offline backups, implementing multi-factor authentication across all systems, and conducting regular security awareness training to prevent initial access via phishing. Furthermore, monitoring for unauthorized data exfiltration and ensuring strict access controls can help mitigate the impact of a potential breach. As attackers continue to target sensitive business and technical information, maintaining a proactive security posture is essential for protecting organizational and stakeholder data.