Electro Marteix Listed by alphv Ransomware Group: Ransomware Claim — What’s Alleged & What To Do

Ransomware groups continue to target mid-sized industrial and service firms across Europe, using double-extortion tactics that combine system encryption with the theft and threatened publication of internal data. Listings on criminal leak sites have become a routine pressure tool in this landscape, even when independent confirmation of the underlying intrusion remains limited.

On 27 February 2024, the ransomware group alphv publicly listed Electro Marteix, a Spanish multi-trade installation company trading as EMTEK. The group claims to have exfiltrated internal files during a ransomware attack. The number of people affected is unknown, and public detail beyond the listing itself is limited. The incident matters because organisations of this type routinely hold operational, client and employee records that can create lasting risk if they leave the organisation’s control.

What happened

According to the available record, Electro Marteix was listed by the alphv ransomware group on 27 February 2024. The group asserts that internal files were exfiltrated as part of a ransomware attack. No further public confirmation of the intrusion method, the precise date of any network compromise, the volume of data taken, or the number of individuals affected has been disclosed. The listing itself constitutes an unverified claim by the threat actor; independent verification of the breach’s full scope is not present in the public facts.

Public reporting on the matter is confined to the organisation’s identity, the date of the listing, and the statement that internal files were taken. Timing of any encryption event, ransom demands, or subsequent data publication remain undisclosed.

Who is alphv?

Alphv, also widely known as BlackCat, is a ransomware-as-a-service operation that emerged in late 2021 and has been documented in numerous public threat-intelligence reports. The group typically operates through affiliates who gain initial access, deploy ransomware written in Rust for cross-platform capability, and pursue double extortion: encrypting systems while simultaneously stealing data and threatening to release it on a dedicated leak site if payment is not made.

Alphv has claimed responsibility for attacks against a range of sectors, including manufacturing, professional services and critical infrastructure suppliers. Its leak site has been used to name victims and, in some cases, to publish sample files as proof of access. Because the group’s claims are self-reported, security researchers treat each listing as an assertion rather than confirmed fact unless corroborated by the victim or independent forensic evidence. In this instance, the facts record only that alphv listed Electro Marteix and claimed the exfiltration of internal files.

Who is Electro Marteix?

Electro Marteix, trading under the name EMTEK, is the commercial identity of ELECTRO MARTEIX, SL, a Spanish company with more than 35 years of experience in the industrial, domestic and service sectors. The firm specialises in the installation and maintenance of electricity, water, gas, heating, air-conditioning, thermal and photovoltaic solar energy systems, telecommunications, public and private lighting, fire-protection systems, and comprehensive maintenance services. It also undertakes energy-saving and new-technology projects for large, medium and small companies as well as private homes, and publicly emphasises a commitment to sustainability.

Companies of this profile sit at the intersection of construction, facilities management and energy services. They typically maintain project documentation, client contracts, site plans, supplier records, employee information and technical drawings. A ransomware incident affecting such an organisation is consequential because disruption can affect ongoing installations and maintenance contracts, while any exposure of internal files may reach both commercial partners and private customers.

What data was at risk

The facts state that internal files were exfiltrated in a ransomware attack. No more granular inventory—such as specific categories of personal data, financial records, or technical documentation—has been disclosed. The exact contents therefore remain unconfirmed.

Organisations operating in electrical, mechanical and energy-installation services commonly hold client contact details, project specifications, invoices, employee personnel files, supplier agreements and site-access information. Whether any of these categories were among the files claimed by alphv cannot be established from the public record. Readers should treat the exposure as limited to the general description “internal files” until further verified information appears.

Why it matters

For individuals whose details may have been present in the company’s systems—employees, residential clients or commercial contacts—the primary risks are identity misuse, targeted phishing and social-engineering attempts that leverage knowledge of real projects or contracts. Even incomplete internal documents can supply enough context for convincing fraud.

For the organisation itself, the consequences include potential operational downtime, contractual obligations to notify affected parties under European data-protection rules, reputational damage among clients who rely on the firm for critical building systems, and the cost of forensic investigation and system recovery. Because the number of people affected is unknown and the precise data types unconfirmed, the full scale of residual risk cannot yet be quantified, but the combination of ransomware encryption and data theft is designed to maximise pressure on the victim.

What to do if you're exposed

If you have had dealings with Electro Marteix or EMTEK—as an employee, contractor or customer—treat the possibility of exposure seriously even while details remain limited. Monitor financial and email accounts for unusual activity, enable multi-factor authentication wherever available, and be sceptical of unsolicited messages that reference the company or recent projects. Consider placing fraud alerts with credit-reference agencies if you believe personal identifiers may have been involved. You can also run a free exposure scan of your email address to check whether it has already appeared in known breach data sets; such a check provides an early indication of whether your information is circulating beyond this single incident.

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