Underground ransomware group lists shengyusteel.com on its leak site

• Ransomware group: Underground
• Country: Taiwan
• Sector: Manufacturing
• Announcement date: April 16, 2025

Underground group claims data breach at Sheng Yu Steel Co., Ltd.

The threat actor known as Underground has listed the Taiwanese manufacturing company shengyusteel.com on its dedicated leak site. According to the announcement made on April 16, 2025, the group claims to have successfully exfiltrated a significant amount of data belonging to the organization. The group alleges that they have obtained approximately 353.9 GB of information from the company's internal systems.

This type of activity is characteristic of modern ransomware operations, which often employ a double extortion tactic. In such scenarios, attackers do not merely encrypt a victim's systems to disrupt operations; they also steal sensitive information to use as leverage. By threatening to release stolen data publicly on a leak site, the threat actors aim to pressure the victim into paying a ransom to prevent the disclosure of confidential corporate or personal information.

Details of the alleged cyberattack

The announcement by the Underground group suggests that the initial compromise may have occurred around April 8, 2025. The group claims that the stolen data is directly related to the core business operations of the company, specifically targeting documents that facilitate manufacturing and distribution processes. The threat actor has threatened to release this information to the public if their demands are not met.

The contents of the alleged leak are extensive and cover various aspects of the company's internal administration and industrial operations. The group claims to possess a wide array of sensitive files, including:

• Company ownership structure documents
• Files from the company president's computer
• HR reports
• Manufacturing material records
• Employee passports
• Employment contracts
• Intellectual property
• Financial documents
• Product development files
• Confidential documents
• Product compliance reports

The breadth of this alleged data theft suggests a deep intrusion into the company's digital infrastructure, potentially touching upon both administrative and operational technology environments.

About Sheng Yu Steel Co., Ltd.

Sheng Yu Steel Co., Ltd. is a steel manufacturing company based in Taiwan. The company operates in the manufacturing and distribution of various steel products, serving as a key player in the regional industrial sector.

Potential impact and industry implications

This incident poses a significant risk to shengyusteel.com due to the sensitive nature of the data claimed to be stolen. The exposure of employee passports and employment contracts presents a direct threat to the individuals involved, as such personal identifiable information (PII) can be utilized for identity theft or highly targeted phishing attacks. Furthermore, the potential disclosure of intellectual property and product development files could lead to a loss of competitive advantage and substantial financial damage to the organization.

Because the company is based in Taiwan, this incident may trigger legal proceedings and regulatory scrutiny under local data protection regulations. For organizations operating in the manufacturing sector, such breaches highlight the critical importance of robust cybersecurity frameworks. Protecting intellectual property and sensitive supply chain data is essential for maintaining market position and trust.

While the specific motivations and technical capabilities of the Underground group remain uncertain due to the limited public information available about them, this event underscores the ongoing threat posed by ransomware groups. Organizations can mitigate these risks by implementing strict access controls, maintaining offline backups, and conducting regular security audits to detect unauthorized access before large-scale data exfiltration can occur.