TEAM GROUP Listed by medusa Ransomware Group: Ransomware Claim — What’s Alleged & What To Do

TEAM GROUP, a major Thai consulting firm, has been listed by the medusa ransomware group as of a report dated September 01, 2025. Public details indicate that internal files were exfiltrated in a ransomware attack, though the number of people affected remains unknown and further specifics about the incident have not been disclosed.

This listing places the organisation among those claimed by medusa on its leak site. For a firm with decades of work on large infrastructure and public projects across Thailand and the region, any confirmed exposure of internal material carries practical consequences for clients, partners and staff, even while independent verification of the full scope stays limited.

Breaking down the breach

According to the available record, TEAM GROUP was listed by the medusa ransomware group on September 01, 2025. The reported summary states that internal files were exfiltrated in a ransomware attack. No figure for the number of people affected has been provided, and details such as the precise date of intrusion, the method of initial access, the volume of data taken, or any ransom demand remain undisclosed in public reporting.

The listing itself constitutes a claim by the group rather than an independently confirmed disclosure by the organisation. Public information does not include statements from TEAM GROUP confirming or denying the incident, nor does it describe any subsequent data publication by medusa. As a result, the factual core is limited to the reported listing and the characterisation of the event as involving exfiltration of internal files under a ransomware attack.

Who is medusa?

Medusa is a ransomware operation that has been active in recent years and is known for a double-extortion model: encrypting systems while also stealing data and threatening to publish it on a dedicated leak site if payment is not made. The group typically lists victims publicly, sometimes with sample files or countdown timers, as a pressure tactic. Its operations have targeted organisations across multiple sectors and countries, often focusing on entities whose data or operational continuity carries commercial or reputational value.

Public reporting on medusa describes it as a Ransomware-as-a-Service style actor that recruits affiliates and maintains an infrastructure for negotiation and data dumping. In this case, the group claims TEAM GROUP as a victim through its listing; no additional claims specific to this organisation—such as particular file counts, financial demands, or published samples—are detailed in the available facts. The listing should therefore be treated as an unverified assertion pending further confirmation or independent evidence.

TEAM GROUP and its sector

TEAM GROUP is described as one of the leading integrated consulting firms in Thailand and the wider region, with more than 40 years of experience. Its work covers comprehensive consulting services in Building and Infrastructure, Water Resources, Environmental Management, Transport and Logistics, and Power and Energy. The firm has completed more than 2,500 projects in Thailand and overseas, including high-profile assignments such as the Xayaburi Hydroelectric Power Project, Suvarnabhumi Airport, the Government Complex, and the MRT Blue Line Extension. It is headquartered at TEAM Building, 151 Nuan Chan Road, Nuan Chan, Bueng Kum, Bangkok 10230.

Consulting firms of this type routinely handle project documentation, engineering designs, environmental assessments, contractual records, client correspondence and internal operational data. Because many of its projects involve public infrastructure, government entities and large private partners, the organisation sits at the intersection of commercial, regulatory and public-interest information. A ransomware incident affecting such a firm is consequential precisely because of the breadth of stakeholders and the sensitivity of planning and delivery materials that typically accompany major civil and energy projects.

What data was at risk

The facts name the exposed material as internal files exfiltrated in a ransomware attack. No further breakdown of file categories, volumes or specific data elements has been disclosed. The number of people affected is listed as unknown.

Organisations of this kind commonly hold project files, technical drawings, environmental studies, financial and contractual records, employee information and client communications. While those categories represent the typical holdings of an integrated consulting practice, the exact contents taken in this incident remain unconfirmed. It is therefore not possible to state with certainty which particular records, if any, were among the exfiltrated material.

What's at stake

For individuals whose information may appear in internal files—employees, contractors or client contacts—the practical risks include potential misuse of personal details for phishing, identity-related fraud or unwanted contact. Because the precise data types and volume are undisclosed, the scale of any such exposure cannot be quantified from public sources.

For TEAM GROUP itself, the stakes involve operational disruption during recovery, possible contractual or regulatory obligations to notify partners and authorities, and reputational effects that can follow any ransomware claim. Clients and project partners may need to reassess shared information or access arrangements. In the infrastructure and energy sectors, even limited leakage of planning or design material can raise competitive or security considerations, though no evidence of such secondary impacts has been reported here. The absence of confirmed victim numbers or published data samples leaves the concrete harm assessment incomplete at present.

Were you affected?

If you have worked with or for TEAM GROUP, or if your details appear in project or contractual records connected to the firm, treat the situation with ordinary caution. Monitor financial and email accounts for unusual activity, enable multi-factor authentication where available, and be alert to unsolicited messages that reference the organisation or its projects. Change passwords on any accounts that may have shared credentials or been used in related systems.

Readers can also run a free exposure scan of their email address to check whether that address has already appeared in known breach data sets. Such checks do not confirm or rule out involvement in this specific incident, but they provide a practical starting point for personal awareness while official details remain limited.

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