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 15, 2025Kaener Personal listed by brotherhoodon the group's public leak site

Data size: 139 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, Kaener Personal is reported in Switzerland, a country with 78 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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Käner Personal

listed as Kaener Personal · Claimed by brotherhood · listed 6 months ago

139 GB

Data size

Age

since listed · data leaked

Status timeline

Listed
Nov 15, 2025
Data leaked

At a glance

Group: brotherhood
Status: Data leaked
Country: Switzerland
Sector: Not Found
Listed on leak site: Nov 15, 2025
Data size: 139 GB

About the victim

AI dossier — public-source company profile

Käner Personal is a Swiss staffing and personnel services company operating since 1967, specialising in temporary staffing, permanent placement, payrolling, and Try & Hire arrangements. The company operates multiple branches across German-speaking Switzerland and other regions including Basel, Bern, Zentralschweiz, and Westschweiz. It serves both job seekers and corporate clients across a wide range of sectors.

Industry: Staffing & Recruitment / Personnel Services
Address: Offices in Baar, Baden, Basel, Uster, Winterthur and Zürich, Switzerland
Founded: 1967

Attack summary

Severity: critical — Käner Personal handles large volumes of sensitive personal data for job candidates and placed workers (PII, employment contracts, payroll records, identification documents) across Switzerland. The confirmed publication of 139 GB of data from a staffing/HR firm constitutes a large-scale regulated PII and financial data breach, meeting the critical threshold.

The Brotherhood ransomware group claims to have exfiltrated 139 GB of compressed data from Käner Personal and has published the data, describing the contents as 'Paid Files'. No encryption claim is explicitly stated; the disclosure status indicates data has been published.

critical

Data the group says was taken

AI dossier — extracted from the leak post

Paid files (139 GB compressed)
Likely employee personal records (PII)
Likely client/placement records
Payroll-related documents

What the group claims

Contains: 139 Gb compressed Paid Files

Sources

Victim sitewww.kaenerpersonal.ch

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.