Disclosure context

About medusalocker

MedusaLocker is a ransomware group that emerged in November 2022, operating with primarily financial motivations and targeting organizations across multiple sectors including technology, energy, healthcare, and manufacturing. The group's origin and specific affiliations remain largely undocumented in public threat intelligence reports, though their operational patterns suggest they may operate as part of the broader ransomware-as-a-service ecosystem that has proliferated in recent years. With 51 documented victims primarily concentrated in the United States, United Arab Emirates, Germany, Canada, and Antigua and Barbuda, MedusaLocker appears to focus on opportunistic targeting rather than specific geographic or sectoral specialization. The group's attack methodology and specific technical capabilities have not been extensively documented by major threat intelligence organizations, though their targeting of critical infrastructure sectors including healthcare and energy suggests they likely employ common ransomware tactics such as network encryption and potential data exfiltration. No major high-profile attacks or significant law enforcement disruptions against MedusaLocker have been publicly reported by CISA, FBI, or other major security agencies. The current operational status of MedusaLocker remains unclear due to limited public documentation, though the relatively recent emergence date suggests the group may still be active or have transitioned to other operations. The group has been linked to 67 public disclosures across our corpus. First observed on a leak site on November 15, 2022; most recent post May 5, 2026. The operation is currently active.

Timeline of this disclosure

May 5, 2026Colegio María Inmaculada (CMI) listed by medusalockeron the group's public leak site

Sector and geography

This disclosure adds to ransomware activity in the Education sector, which has 694 disclosures indexed across all operators we track. Geographically, Colegio María Inmaculada (CMI) is reported in CR.

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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Colegio María Inmaculada (CMI)

Claimed by medusalocker · listed 15 days ago

15d

Age

since listed · data leaked

Status timeline

Listed
May 5, 2026
Data leaked

At a glance

Group: medusalocker
Status: Data leaked
Country: CR
Sector: Education
Listed on leak site: May 5, 2026

About the victim

AI dossier — public-source company profile

Colegio María Inmaculada (CMI) is a Catholic school located in Moravia, Costa Rica, operating under the domain mariainmaculada.ed.cr. It provides primary and/or secondary education in the Costa Rican school system. The public website was not accessible at time of analysis, returning only a 'Coming Soon' placeholder page.

Industry: Primary & Secondary Education (Catholic School)
Address: Moravia, San José, Costa Rica

Attack summary

Severity: high — Data is stated as published (data_published) following compromise of multiple internal servers including a domain controller, implying credential and directory data exfiltration from an educational institution likely holding student and staff PII. The involvement of a DC suggests broad network access and potential exposure of regulated personal data for minors.

MedusaLocker claims to have compromised the school's internal network infrastructure, identifying multiple servers (CMI-DC01, CMI-APP, CMI-HTTP2, main-server1/2) and the local domain cmi.local. The post is listed under 'data_published' status, suggesting exfiltration occurred, though no specific data categories or volume are described in the post.

high

Data the group says was taken

AI dossier — extracted from the leak post

Active Directory domain data (cmi.local)
Domain controller contents (CMI-DC01)
Application server data (CMI-APP)
Web server data (CMI-HTTP2)
General server data (main-server1, main-server2)

What the group claims

Catholic school in Moravia, Costa Rica. Domain cmi.local / mariainmaculada.ed.cr. Servers: CMI-DC01, CMI-APP, CMI-HTTP2, main-server1/2.

The leak post

captured from the group's site

File Manager File Manager home page BARAAAI Data is being prepared for publication. BAPAMAI Data is being prepared for publication. BAUARAI Data is being prepared for publication. BAVADAI Data is being prepared for publication. BAVACAI Data is being prepared for publication. BAVAQAI Data is being prepared for publication. Raycolighting DEMO 3137 S Alameda Street, Los Angeles, CA 90058, USA $10 000 Organization with 2 emails extracted. Domain: raycolighting.com baralai Data is being prepared for publication. CEAGESP / Netfeirasp DEMO São Paulo, Brazil $20 000 Brazilian produce wholesale market network. Domain netfeirasp.ceagesp (CEAGESP). Also demarchibrasil.com.br accounts. Colegio María Inmaculada (CMI) DEMO Moravia, San José, Costa Rica $50000 Catholic school in Moravia, Costa Rica. Domain cmi.local / mariainmaculada.ed.cr. Servers: CMI-DC01, CMI-APP, CMI-HTTP2, main-server1/2. Académie de Montpellier / CSJM DEMO Béziers, Occitanie, France $15000 French public school network. Domain CSJM.BEZIERS, part of Académie de Montpellier (ac-montpellier.fr). Occitanie region (laregion.fr). Teacher and admin staff credentials. Palmers Relocations DEMO Victoria, Australia $63 000 Australian …

Sources

Victim sitemariainmaculada.ed.cr
Leak posthttp://t33zoj4qwv455fog7qnb2azi5xcdxkixughmmduzbw2rtdgryqfbh6id.onion/company/baratai/

Source

Indexed 15 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.