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, 2026ActionAid / TACOSA listed by medusalockeron the group's public leak site

Sector and geography

This disclosure adds to ransomware activity in the Public Sector sector, which has 259 disclosures indexed across all operators we track. Geographically, ActionAid / TACOSA is reported in GB, a country with 309 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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ActionAid / TACOSA

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: GB
Sector: Public Sector
Listed on leak site: May 5, 2026

About the victim

AI dossier — public-source company profile

ActionAid International is a global federation operating in over 40 countries across Africa, Asia, Europe, and the Americas, working to end poverty and injustice with a particular focus on women's rights, land and climate, politics and economics, and emergency response. TACOSA (tacosa.org.za) appears to be an affiliated South African entity, and the post also references immigration.go.tz, a Tanzanian government domain. The federation employs teams worldwide and runs campaigns, advocacy, and direct humanitarian programming.

Industry: International Non-Governmental Organisation (NGO) / Humanitarian Aid
Address: Vereniging ActionAid International, registered in Netherlands (RSIN: 813342211, Reg: 27264198); global federation headquartered internationally with UK presence

Attack summary

Severity: critical — The attack spans an international NGO, a South African affiliate, and a Tanzanian government immigration portal (immigration.go.tz), the latter of which is a government/public-sector system likely containing PII and immigration records at scale. Data is confirmed published, constituting exfiltration of potentially regulated government and beneficiary personal data across multiple jurisdictions.

MedusaLocker claims to have compromised ActionAid and affiliated domains (actionaid.org, tacosa.org.za, immigration.go.tz), with the disclosure status recorded as data_published, indicating exfiltration and publication of data rather than encryption alone.

critical

Data the group says was taken

AI dossier — extracted from the leak post

Organisational data from actionaid.org
Data from TACOSA (tacosa.org.za)
Data from Tanzanian immigration portal (immigration.go.tz)

What the group claims

NGO sector. Domains: actionaid.org, tacosa.org.za, immigration.go.tz.

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 siteactionaid.org
Leak posthttp://t33zoj4qwv455fog7qnb2azi5xcdxkixughmmduzbw2rtdgryqfbh6id.onion/company/actionaid-tacosa/

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.