Disclosure context

About brotherhood

The Brotherhood ransomware group is a recently emerged financially-motivated cybercriminal organization first observed in October 2025, representing one of the newer entrants in the ransomware landscape. Given the group's recent emergence and limited public documentation from major security firms and law enforcement agencies, detailed information about their origin, country of operation, and specific affiliations remains largely unknown to open-source intelligence. Based on observed targeting patterns, the group appears to employ opportunistic attack methodologies, focusing primarily on English-speaking markets including the United States, Australia, and Canada, while also targeting victims in Germany and Switzerland, suggesting either broad-spectrum initial access capabilities or acquisition of access through underground markets. Their victim selection spans multiple sectors including business services, construction, transportation and logistics, and technology companies, indicating a non-discriminatory approach typical of many financially-motivated ransomware operations rather than targeted campaigns against specific industries. With only 18 documented victims since their October 2025 emergence, Brotherhood represents a relatively small-scale operation compared to established ransomware groups, and specific details regarding their encryption methods, data exfiltration practices, or extortion tactics have not been publicly documented by major threat intelligence providers. The group remains active as of the latest available intelligence, though their limited operational footprint and recent emergence means comprehensive analysis of their tactics, techniques, and procedures awaits further documentation by security researchers and law enforcement agencies. The group has been linked to 18 public disclosures across our corpus. First observed on a leak site on October 10, 2025; most recent post January 6, 2026. The operation is currently active.

Timeline of this disclosure

November 28, 2025Ingenieurbüro Laudi listed by brotherhoodon the group's public leak site

Data size: 4 GB

Sector and geography

This disclosure adds to ransomware activity in the Not Found sector, which has 4,859 disclosures indexed across all operators we track. Geographically, Ingenieurbüro Laudi is reported in Germany, a country with 695 ransomware disclosures in our corpus.

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.

Ransomware victim disclosure

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Ingenieurbüro Laudi

Claimed by brotherhood · listed 6 months ago

4 GB

Data size

Age

since listed · data leaked

Status timeline

Listed
Nov 28, 2025
Data leaked

At a glance

Group: brotherhood
Status: Data leaked
Country: Germany
Sector: Not Found
Listed on leak site: Nov 28, 2025
Data size: 4 GB

About the victim

AI dossier — public-source company profile

Ingenieurbüro Laudi is a German engineering consultancy specialising in technical building equipment (TGA), including HVAC, sanitary, sprinkler, electrical engineering, and building automation. The firm offers planning, construction supervision, quality assurance, and consulting services to building owners and developers. It operates from three offices in Essen (headquarters), Attendorn, and Soest in North Rhine-Westphalia.

Industry: Building Services Engineering (TGA / HVAC & Electrical Planning)
Address: Essen, North Rhine-Westphalia, Germany (main office); also Attendorn and Soest, Germany
Employees: 11-50

Attack summary

Severity: high — 143 GB total compressed data has been exfiltrated and partially published; the firm handles detailed building plans and client data that likely include sensitive project and business information at significant scale, constituting confirmed exfiltration of substantial business data.

The 'brotherhood' ransomware group claims to have exfiltrated data from Ingenieurbüro Laudi, publishing 4 GB of compressed files freely and holding 139 GB of compressed files behind a paywall, indicating both exfiltration and likely encryption occurred.

high

Data the group says was taken

AI dossier — extracted from the leak post

Project planning documents
Construction supervision records
Client/building owner data
Technical engineering files
Internal business documents

What the group claims

Contains: 4 Gb Compressed Free Files, 139 Gb Compressed Paid Files

Sources

Victim sitewww.ib-laudi.de

Source

Indexed 6 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.