San Jose Country Club Listed by medusa Ransomware Group: Ransomware Claim — What’s Alleged & What To Do

San Jose Country Club, a private golf club in Northern California, has been listed by the medusa ransomware group as a victim of a ransomware attack involving the exfiltration of internal files. The listing was reported on June 09, 2025. Public detail remains limited: the number of people affected is unknown, and no further confirmation of the incident has been provided beyond the group's claim.

This matters because private clubs routinely hold membership records, contact details, financial information and operational documents. Even when exact contents are unconfirmed, any exposure of internal files can create lasting risk for members, staff and the organisation itself.

What happened

According to the available record, San Jose Country Club was listed by the medusa ransomware group on or around June 09, 2025. The group claims that internal files were exfiltrated during a ransomware attack. No public information has been released about the precise date of intrusion, the method of access, the volume of data taken, or whether systems were encrypted. The number of individuals affected is listed as unknown. The listing itself constitutes an unverified claim by the threat actor; independent confirmation of the breach has not been detailed in the public record.

Inside medusa

Medusa is a well-documented ransomware operation that has been active for several years. Like many modern ransomware groups, it typically follows a double-extortion model: after gaining access to a network, operators exfiltrate data and then encrypt systems, threatening to publish the stolen material on a dedicated leak site if a ransom is not paid. The group has previously targeted organisations across multiple sectors, including healthcare, education, manufacturing and professional services, and routinely posts victim names and sample files to pressure payment. Its leak-site listings are public claims rather than independently Reported Facts. In this case, the record states only that San Jose Country Club appears on that listing in connection with exfiltrated internal files; no additional statements attributed specifically to this victim have been provided.

About San Jose Country Club

San Jose Country Club is a premier family-friendly private golf club located in Northern California and established in 1899. It is known for its long tradition and serves members in the Bay Area with year-round golf, dining options and social activities. The club features a newly remodeled clubhouse and event facilities used for weddings and special events, and it emphasises service and exclusive dining. Its headquarters address is listed as 15571 Alum Rock Ave, San Jose, CA 95127. Private clubs of this type typically maintain membership databases, billing and payment records, employee information, event contracts and internal operational documents. A ransomware incident at such an organisation can therefore affect both the club’s day-to-day operations and the personal information of members and staff.

What was likely exposed

The available facts state that internal files were exfiltrated in a ransomware attack. Exact data types beyond that description have not been disclosed, and the number of people affected remains unknown. Organisations of this kind commonly hold the following categories of information; whether any of these were among the files taken is unconfirmed:

• Membership applications, directories and contact details
• Billing, payment and financial records
• Employee and contractor personal data
• Event contracts, guest lists and catering records
• Internal operational and administrative documents

Because the precise contents have not been confirmed, any assessment of what was actually taken must remain provisional.

What's at stake

For individuals whose information may have been among the internal files, the primary risks include identity theft, phishing and social-engineering attempts that use accurate personal or financial details, and unwanted contact. Members and staff could face fraudulent charges or account takeovers if payment data or credentials were present. For the club itself, consequences can include operational disruption, reputational harm among members, potential regulatory notification obligations, and the cost of investigation and remediation. Because the scale of the exposure is unknown, the full extent of these risks cannot yet be measured. The absence of confirmed numbers does not eliminate the possibility of harm; it simply means affected parties must treat the situation with caution until more detail emerges.

Were you affected?

If you are a current or former member, employee, contractor or guest of San Jose Country Club, treat the possibility of exposure seriously even though public detail is limited. Monitor financial accounts and credit reports for unexpected activity, be alert to phishing messages that reference the club or personal details, and consider placing a fraud alert with the major credit bureaus. Change passwords for any accounts that may have reused credentials associated with club services. Readers can also run a free exposure scan of their email address to check whether their information has already appeared in known breach data sets. Continue to watch for official notices from the club itself, as further Reported Details may be released over time.

AICompiled with AI assistance from public sources and published under our editorial standards.