Disclosure context

About kazu

The Kazu ransomware group is a relatively new threat actor that emerged in November 2025, operating with apparent financial motivations based on their targeting patterns across multiple sectors and geographic regions. Given their recent emergence and limited public documentation, details about their country of origin and potential affiliations remain unclear, though their targeting of diverse international victims suggests either a ransomware-as-a-service model or an independent operation with broad reach capabilities. With only nine documented victims to date, specific details about Kazu's attack methodology, initial access vectors, and encryption techniques have not been extensively documented by major threat intelligence organizations, though their targeting spans healthcare, public sector, financial services, and technology organizations across the United States, Colombia, South Africa, Nigeria, and Great Britain. The group's recent emergence means there are no widely reported major campaigns or high-profile incidents documented by established security research organizations like Mandiant, CISA, or the FBI. As of the latest available intelligence, Kazu appears to remain active given their very recent first observation date, though their limited victim count and recent emergence make definitive assessments of their operational status preliminary. The group has been linked to 13 public disclosures across our corpus. First observed on a leak site on November 11, 2025; most recent post May 21, 2026. The operation is currently active.

Timeline of this disclosure

May 19, 2026HT Médica listed by kazuon the group's public leak site

Sector and geography

This disclosure adds to ransomware activity in the Healthcare sector, which has 1,779 disclosures indexed across all operators we track. Geographically, HT Médica is reported in Spain, a country with 212 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

← All victims

HT Médica

Claimed by kazu · listed 2 days ago

Age

since listed · listed for ransom

Status timeline

Listed
May 19, 2026

Current state: Listed for ransom

At a glance

Group: kazu
Status: Listed for ransom
Country: Spain
Sector: Healthcare
Listed on leak site: May 19, 2026

About the victim

AI dossier — public-source company profile

HT Médica is a healthcare company based in Spain. Based on the sector classification and name, it likely operates medical clinics or health services. No additional detail is available from a public site excerpt.

Industry: Healthcare Services

Attack summary

Severity: medium — The victim operates in the healthcare sector, which typically involves regulated personal and medical data. However, no proof files, data size, or specific data types are confirmed, warranting medium rather than critical severity.

The group 'kazu' claims a data breach against HT Médica in Spain, listing it alongside several other victims. No details on encryption, exfiltration volume, or specific data types are provided in the post.

medium

What the group claims

Data breach

The leak post

captured from the group's site

A847 8A8C E2A4 3B58 FB12 D678 3BA4 C334 C85C EE56
HealthDaq Dublin based healthcare recruitment platform Data Breach
Spain - HT Médica Data breach
Peru - Natclar (S.G. Natclar S.A.C.)
SA - Gauteng Provincial Government
Statistics South Africa – Official National Data and Insights Portal

Sources

Leak posthttp://6czlbd2jfiy6765fbnbnzuwuqocg57ebvp3tbm35kib425k4qnmiiiqd.onion

Source

Indexed 2 days 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.