Leyhausen Research listed on Qilin ransomware leak site

• Ransomware group: Qilin
• Country: Germany
• Sector: Professional Services
• Announcement date: October 15, 2025

The Qilin ransomware group has listed the German-based organization Leyhausen Research on its dedicated leak site. This announcement, published on October 15, 2025, constitutes a claim of a data breach against the professional services firm.

The details of the claim

According to the announcement made by the Qilin group, the organization has been targeted in a cyberattack. The group has officially listed Leyhausen Research on its leak site, claiming that they have successfully breached the institution. In the announcement, the threat actors indicate that they may proceed to publish the institution's data on the internet.

Ransomware groups often utilize leak sites to exert pressure on their victims. These platforms serve as a public gallery where the group displays the names of targeted organizations to increase visibility and urgency. By threatening to release sensitive information, the attackers aim to coerce the victim into meeting their demands. This tactic is a hallmark of modern cyber extortion, where the threat of public exposure is used as a primary lever for negotiation.

Information regarding the alleged breach

Regarding the specifics of the incident, the announcement does not provide detailed information concerning the nature of the leaked data. The group has not specified the volume of data involved or the specific types of files that were allegedly exfiltrated. The only information available in the announcement's supporting materials is a screenshot containing general corporate information about the institution.

The listing names no specific data types that have been compromised.

About Leyhausen Research

Leyhausen Research is an international market research company that has been operating since 1996. The firm provides a variety of field research and data collection services across multiple global regions, including Europe, the Middle East, India, and Africa. To facilitate its professional research solutions, the company utilizes various operational methods, such as call centers and field operations, to serve a diverse range of industries.

Risk assessment and industry implications

This incident may pose significant risks to the operational continuity of the institution and could potentially lead to the exposure of sensitive corporate data. Because Leyhausen Research is based in Germany, a potential data breach of this nature may trigger legal sanctions and mandatory notification obligations under the General Data Protection Regulation (GDPR). Organizations operating within the European Union must adhere to strict protocols regarding the protection of personal data and the timely reporting of breaches to regulatory authorities.

Given that the Qilin group is known for employing a double-extortion method, there is a high likelihood that any leaked data could be utilized in secondary attacks or targeted phishing campaigns. In a double-extortion scenario, attackers not only encrypt the victim's systems but also steal sensitive data to use as leverage. This significantly expands the attack surface, as the stolen information can be used to target the organization's clients and business partners, creating indirect risks across the entire supply chain.

The activities of the Qilin group, which have been observed since 2022, suggest that threats against institutions of a similar scale may persist. For organizations in the professional services and research sectors, maintaining robust security postures is essential. Common defensive steps include implementing multi-factor authentication, maintaining rigorous patch management schedules, and conducting regular employee awareness training to mitigate the risk of phishing. Furthermore, ensuring comprehensive data backup strategies and monitoring network traffic for unusual patterns can help organizations detect and respond to unauthorized access more effectively.