Cyber Incident Victim: CIUSSS de l'Est-de-l'Île-de-Montréal
Date:
May 2021
Location:
Canada
Summary
A cybersecurity breach at CIUSSS de l'Est-de-l'Île-de-Montréal compromised sensitive personal information belonging to approximately 2,300 individuals. Hackers infiltrated the organization's systems, stealing private data and exposing affected parties to potential privacy risks. The incident disrupted operations and necessitated an investigation into the attack's scope while prompting efforts to secure compromised records and address vulnerabilities. Mitigation measures were implemented to prevent further unauthorized access and protect impacted individuals from potential misuse of their stolen information.
| CIA Posture | Motives | Tactics, Techniques & Procedures |
|---|---|---|
| Available to members | 1 motive | 1 technique |
| Threat Actors | Type | Location |
|---|---|---|
| 0 actors | Available to members | Available to members |
Description
The CIUSSS de l'Est-de-l'Île-de-Montréal, a healthcare and social services network in Montreal, experienced a cybersecurity incident around May 31, 2021, involving unauthorized access to its systems. Attackers exfiltrated personal data belonging to approximately 2,300 individuals, including both patients and employees. The compromised information included names, addresses, social insurance numbers, and medical details, creating significant privacy risks. The breach was discovered during routine security monitoring, prompting immediate containment measures. CIUSSS took affected systems offline to prevent further data loss and launched a forensic investigation with third-party cybersecurity experts. Authorities, including Quebec's access-to-information commission and law enforcement, were notified as required by breach disclosure regulations.
The incident caused operational disruptions to patient services and administrative functions during the containment phase. CIUSSS established a dedicated support line for affected individuals and offered credit monitoring services to mitigate identity theft risks. Internal communications emphasized staff vigilance against phishing attempts leveraging stolen data. No ransomware deployment or public extortion demands were explicitly confirmed in official statements, though the breach’s scope suggested potential financial motives. Recovery efforts focused on restoring secure system access while auditing network vulnerabilities. The organization faced regulatory scrutiny regarding data protection practices, with particular attention to safeguards for sensitive health information. Service delivery resumed gradually following security validation, though long-term reputational and compliance impacts persisted.