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Medibank

listed as medibank.com.au · Claimed by Revil · listed 4 years ago

44m
Age
since listed · data leaked

Status timeline

  1. ListedNov 7, 2022
  2. Data leakeddate unknown

At a glance

Group
Revil
Status
Data leaked
Country
Australia
Sector
Financial Services
Listed on leak site
Nov 7, 2022

About the victim

AI dossier — public-source company profile

Medibank is one of Australia's largest private health insurers, providing health insurance products and services to approximately 3.7 million customers across Australia. The company operates under both the Medibank and ahm Health Insurance brands and is listed on the Australian Securities Exchange. It also offers a range of health and wellbeing services beyond insurance.

Industry
Private Health Insurance
Address
720 Bourke Street, Docklands, Victoria 3008, Australia
Employees
3000-4000
Founded
1976

Attack summary

Severity: critical — Medibank is a major health insurer; the publicly documented breach involved exfiltration of sensitive medical and PII data for millions of Australian customers, constituting a large-scale regulated data disclosure involving health records.

The REvil group claims to have attacked Medibank and the disclosure status is listed as data_published, indicating that stolen data has been released. The attack is consistent with publicly documented events in which sensitive customer health and personal data was exfiltrated.

critical

Data the group says was taken

AI dossier — extracted from the leak post
  • Customer personally identifiable information (PII)
  • Health claims data
  • Medical records
  • Policy and membership details
  • Contact and address information
  • Date of birth records
  • Medicare card numbers

Sources

Source

Indexed 4 years 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.

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Disclosure context

About Revil

REvil, also known as Sodinokibi, was a highly sophisticated ransomware-as-a-service operation that emerged in April 2019 and quickly became one of the most prolific and financially successful cybercriminal organizations, primarily motivated by financial gain. The group is believed to have originated from Russia, operating as a RaaS model where core developers rented their ransomware tools to affiliate criminals, and maintained connections to the now-defunct GandCrab ransomware operation with some researchers suggesting personnel overlap. REvil primarily gained initial access through exploiting vulnerabilities in remote desktop protocol implementations, phishing campaigns, and supply chain attacks, employing double extortion tactics where they exfiltrated sensitive data before encryption and threatened to publish it on their "Happy Blog" leak site if ransoms were not paid, using advanced encryption methods that made file recovery nearly impossible without payment. The group conducted several high-profile attacks including the devastating supply chain attack against Kaseya in July 2021 that affected thousands of downstream customers, attacks on major corporations like JBS Foods, and demanded ransoms reaching up to $70 million, ultimately leading to increased law enforcement attention and pressure from international authorities. Following coordinated law enforcement actions and mounting pressure from the U.S. and Russian governments in late 2021, REvil's infrastructure was taken down and the group ceased operations, with several suspected members reportedly arrested by Russian authorities. The group has been linked to 96 public disclosures across our corpus. First observed on a leak site on August 26, 2019; most recent post November 28, 2022. The operation is currently inactive.

Also tracked as: Sodinokibi.

Timeline of this disclosure

  • November 7, 2022medibank.com.au listed by Revilon the group's public leak site

Other recent disclosures by Revil

Revil has been linked to 96 public victims on Darkfield. A sample of the most recent:

See the full Revil dossier →

Sector and geography

This disclosure adds to ransomware activity in the Financial Services sector, which has 1,184 disclosures indexed across all operators we track. Geographically, medibank.com.au is reported in Australia, a country with 455 ransomware disclosures in our corpus.

If your organisation is affected

A listing by Revil means medibank.com.au appeared on a ransomware extortion site and data attributed to it has been published. If this is your organisation, or a supplier you depend on, the priority is to confirm the intrusion and contain it before the window to act closes.

  • Engage your incident-response team and preserve forensic evidence before remediating — do not wipe affected systems first.
  • Force a password reset and revoke active sessions for exposed accounts; rotate any credentials, API keys or certificates that may have been in the stolen data.
  • Assess regulatory notification duties (GDPR, NIS2, sector regulators) — many carry a 72-hour reporting clock from awareness.
  • Report the incident to your national CERT, ACSC (Australia), as required for your jurisdiction.
  • Monitor for the data appearing on Revil's leak site and across paste and breach channels, and brief downstream partners who may be exposed through you.

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.