Presort First Class targeted by Medusa ransomware group

• Ransomware group: Medusa
• Country: United States
• Sector: Professional Services
• Announcement date: June 1, 2025

Medusa ransomware group claims data breach at Presort First Class

The Medusa ransomware group has published a leak announcement on their dedicated leak site, claiming to have stolen a significant amount of data belonging to the organization Presort First Class. According to the announcement, the threat actor group has made the alleged stolen information available for public access on their platform.

Details of the alleged attack and ransom demand

The Medusa group issued a leak announcement regarding Presort First Class on May 27, 2025. The group claims to have successfully infiltrated the organization's networks and obtained a total of 279.30 GB of data. Following the initial intrusion, the attackers have published this data on their leak site as part of their extortion process.

In addition to the data leak, the announcement includes a specific financial demand. The Medusa group has listed a ransom demand of 100,000 USD. This type of tactic is characteristic of modern ransomware operations, where attackers pressure victims through the threat of publicizing sensitive information.

Data types and contents identified in the leak

The information released by the threat actors appears to contain highly sensitive documentation. Based on screenshots provided by the group, the leaked data includes samples of various financial and administrative documents. Specifically, the content includes:

• Payroll data
• Tax records
• Financial documents

The presence of these documents suggests that the breach involves sensitive internal information that could impact the privacy of individuals associated with the organization.

About Presort First Class

Presort First Class is a professional services firm based in Oklahoma City, USA. The company provides a comprehensive array of services, including design, print, and mail services. The organization operates with a workforce of approximately 85 employees.

Analysis and potential organizational impact

The Medusa group is recognized as a Ransomware-as-a-Service (RaaS) entity that has been active since 2021. This group is known for employing double extortion tactics, a method where attackers not only encrypt an organization's data but also threaten to leak sensitive information on a public leak site to increase pressure on the victim.

The alleged leak of this data may lead to the exposure of personal information and financial records belonging to the organization's employees. Because the organization operates within the United States, the incident may result in scrutiny under state-level data protection regulations and could potentially lead to legal consequences. Furthermore, the publication of such data can increase secondary risks for the affected individuals, such as the threat of identity theft and the likelihood of targeted phishing attacks.

For organizations in the professional services sector, such incidents can result in negative impacts on operational continuity and corporate reputation. To defend against such threats, organizations typically focus on implementing robust security measures, such as multi-factor authentication, regular data backups, and continuous monitoring of network traffic to detect unauthorized access. Maintaining a strong incident response plan is also a critical component of modern cybersecurity defense strategies.