Was Nuclebrás Equipamentos Pesados hit by ransomware?

Nuclebrás Equipamentos Pesados was listed by the worldleaks ransomware operation (Brazil), and stolen data was published on the group's leak site. Darkfield tracks this disclosure with the original leak post, screenshot and group context.

Who is the worldleaks ransomware group?

worldleaks is a ransomware operator tracked by Darkfield. See the full operator dossier for its known victims, sectors targeted, IOCs and leak-site infrastructure.

What data was leaked in the Nuclebrás Equipamentos Pesados breach?

worldleaks published data attributed to Nuclebrás Equipamentos Pesados. Darkfield captured the leak post and a screenshot of the listing.

Ransomware victim disclosure

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Nuclebrás Equipamentos Pesados

Claimed by Worldleaks · listed 8 months ago

Age

since listed · data leaked

Status timeline

ListedNov 22, 2025
Data leakeddate unknown

At a glance

Group: Worldleaks
Status: Data leaked
Country: Brazil
Sector: Manufacturing
Listed on leak site: Nov 22, 2025

About the victim

AI dossier — public-source company profile

Nuclebrás Equipamentos Pesados S.A. (NUCLEP) is a Brazilian state-owned company under the Ministry of Science, Technology, Innovation, and Communications, founded in 1975 and headquartered in Itaguaí, Rio de Janeiro. NUCLEP manufactures heavy, large-scale industrial equipment primarily for nuclear power plants, offshore oil platforms, submarine construction, and energy transmission infrastructure. Its facility covers 1.5 million square metres with 85,000 m² of production floor and a private port terminal capable of handling indivisible loads up to 1,000 tonnes.

Industry: Heavy Equipment Manufacturing for Nuclear, Defence & Energy
Address: Município de Itaguaí, Estado do Rio de Janeiro, Brazil
Founded: 1975

Attack summary

Severity: critical — NUCLEP is a Brazilian state-owned company directly involved in nuclear power equipment manufacturing, submarine construction, and national defence programmes. Any confirmed data exfiltration from such an entity constitutes a critical-severity incident due to the potential exposure of regulated, strategically sensitive, and national-security-relevant information.

The worldleaks group claims to have attacked NUCLEP and has published data (disclosed status: data_published); the leak post does not specify ransom demand or data volume, but the disclosure implies exfiltration of internal company data from a strategically sensitive Brazilian state-owned defence and nuclear equipment manufacturer.

critical

Data the group says was taken

AI dossier — extracted from the leak post

Internal company documents
Procurement and contract records
Financial data
Employee information
Operational/industrial data

Original description

AI-summarised, not from the leak post

"Nuclebrás Equipamentos Pesados S.A. (NUCLEP) is a Brazilian state-owned company under the Ministry of Science, Technology, Innovation, and Communications. Founded in 1975, NUCLEP is responsible for developing and manufacturing heavy equipment, especially for nuclear power plants. Besides serving the nuclear sector, it also provides solutions for offshore oil platforms and submarine construction, acting as a key player in the Brazilian technological and industrial development."

Sources

Victim sitewww.nuclep.gov.br
Leak posthttps://worldleaksartrjm3c6vasllvgacbi5u3mgzkluehrzhk2jz4taufuid.onion/companies/8007568416

Source

Indexed 8 months ago

This page surfaces a public ransomware disclosure indexed by Darkfield. Original posts come from the operator's own leak site; we cross-check against ransomware.live, RansomLook and RansomWatch where applicable. Share this URL freely.

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Disclosure context

About worldleaks

Based on the limited available data, worldleaks is a recently emerged ransomware group that was first observed in May 2025 and appears to be primarily financially motivated, having claimed 134 victims in a relatively short timeframe since its emergence. The group's origin and organizational structure remain unclear, with no publicly documented information from major cybersecurity firms or law enforcement agencies regarding their country of origin, potential affiliations, or operational model. Their targeting patterns indicate a focus on English-speaking countries, particularly the United States, United Kingdom, and Canada, with additional activity observed in Germany and Japan, while their sector targeting shows a preference for healthcare, technology, manufacturing, and consumer services organizations. Due to the group's recent emergence and limited public documentation by established threat intelligence sources, specific details about their attack methodologies, encryption techniques, extortion tactics, and notable campaigns have not yet been comprehensively analyzed or reported by organizations such as CISA, FBI, or major cybersecurity research firms. The group appears to remain active as of the most recent observations, though comprehensive threat intelligence profiling awaits further analysis and documentation by established cybersecurity authorities. The group has been linked to 173 public disclosures across our corpus. First observed on a leak site on May 18, 2025; most recent post July 2, 2026. The operation is currently active.

Timeline of this disclosure

November 22, 2025Nuclebrás Equipamentos Pesados listed by worldleakson the group's public leak site

Other recent disclosures by worldleaks

worldleaks has been linked to 173 public victims on Darkfield. A sample of the most recent:

See the full worldleaks dossier →

Sector and geography

This disclosure adds to ransomware activity in the Manufacturing sector, which has 3,681 disclosures indexed across all operators we track. Geographically, Nuclebrás Equipamentos Pesados is reported in Brazil, a country with 404 ransomware disclosures in our corpus.

If your organisation is affected

A listing by worldleaks means Nuclebrás Equipamentos Pesados appeared on a ransomware extortion site and data attributed to it has been published. If this is your organisation, or a supplier you depend on, the priority is to confirm the intrusion and contain it before the window to act closes.

Engage your incident-response team and preserve forensic evidence before remediating — do not wipe affected systems first.
Force a password reset and revoke active sessions for exposed accounts; rotate any credentials, API keys or certificates that may have been in the stolen data.
Assess regulatory notification duties (GDPR, NIS2, sector regulators) — many carry a 72-hour reporting clock from awareness.
Report the incident to your national CERT, CERT.br (Brazil), as required for your jurisdiction.
Monitor for the data appearing on worldleaks's leak site and across paste and breach channels, and brief downstream partners who may be exposed through you.

How we know this. Darkfield monitors public ransomware leak sites continuously, archiving every new disclosure and the data later released against the victim. Each entry on this page is sourced from the operator's own publication and cross-checked against complementary OSINT feeds (RansomLook, ransomware.live, RansomWatch). We do not collect or host stolen data — only the metadata, timestamps and screenshots needed to make the public disclosure searchable and accountable. Records here are corrected when the original post is edited, retracted, or merged with another disclosure.