Executive Summary

Freedom Mobile, Canada's fourth-largest wireless carrier, has disclosed a data breach that exposed the personal information of a subset of its customers. The company announced on December 3, 2025, that it detected the unauthorized access on October 23, 2025. The investigation revealed that the threat actor gained entry by using a compromised account belonging to one of the company's subcontractors. The exposed data includes customer Personally Identifiable Information (PII) such as names, addresses, and dates of birth. Freedom Mobile has stated that financial information and account passwords were not compromised. The company is in the process of notifying affected customers and has implemented additional security measures to secure its platform.

Threat Overview

This incident is a classic example of a supply chain attack, where an organization is breached through a trusted third-party vendor or partner. The attack vector was a compromised account of a subcontractor, which highlights the security risks associated with third-party access to sensitive systems.

• Attack Vector: The attacker used legitimate, albeit stolen, credentials from a subcontractor to log into Freedom Mobile's customer account management platform.
• Attacker Objective: The primary objective appears to have been data theft for the purpose of identity fraud or targeted phishing campaigns.
• Incident Response: Upon detection, Freedom Mobile blocked the compromised accounts and suspicious IP addresses and engaged in remediation efforts.

Technical Analysis

The core of this attack lies in the exploitation of trusted relationships, a technique tracked by MITRE as T1199 - Trusted Relationship. By compromising a subcontractor, the attacker bypassed perimeter defenses and appeared as a legitimate user. Once inside, they likely used the platform's intended functionality to access and exfiltrate customer data.

The exposed data includes:

• Full Names
• Home Addresses
• Dates of Birth
• Phone Numbers
• Freedom Mobile Account Numbers

Crucially, the company asserts that passwords, PINs, and credit card information were not accessed, which significantly reduces the risk of immediate financial fraud. However, the stolen PII is more than sufficient to conduct sophisticated social engineering and phishing attacks.

Impact Assessment

While Freedom Mobile describes the number of affected customers as 'limited', the impact on those individuals could be significant. The stolen data is a valuable commodity for cybercriminals and can be used for:

• Targeted Phishing (Spear Phishing): Attackers can use the stolen account details to craft highly convincing phishing emails or SMS messages (smishing) pretending to be from Freedom Mobile or another trusted entity.
• Identity Theft: The combination of name, address, and date of birth is often enough to attempt to open fraudulent accounts or pass identity verification checks.
• SIM Swapping Attacks: While PINs were not exposed, the other personal data could be used to socially engineer customer service representatives to perform an unauthorized SIM swap, giving attackers control over the victim's phone number.

For Freedom Mobile, the breach results in reputational damage, customer churn, and the costs associated with incident response, legal fees, and potential regulatory fines.

Detection & Response

• Third-Party Access Monitoring: Organizations must rigorously monitor all access from third-party accounts. This includes baselining normal activity and alerting on deviations, such as logins from unusual IP addresses, access at odd hours, or an unusually high volume of data access. D3FEND's D3-UGLPA: User Geolocation Logon Pattern Analysis is a relevant technique.
• Least Privilege Principle: Subcontractor accounts should be strictly limited to accessing only the data and systems absolutely necessary for their job function. This can limit the blast radius if an account is compromised.
• Customer Notification: Affected customers should be advised to enable multi-factor authentication on their Freedom Mobile accounts and be extremely cautious of any unsolicited communications asking for personal information.

Mitigation

1. Enforce MFA for Third Parties: Mandate the use of multi-factor authentication for all third-party and subcontractor accounts that have access to internal systems or customer data. This is the single most effective control against credential compromise.
2. Vendor Risk Management: Implement a comprehensive third-party risk management program. This should include security assessments of all subcontractors before granting them access and periodic reviews of their security posture.
3. Network Segmentation: Isolate the systems that third parties can access from the rest of the corporate network. This prevents a compromise in one area from spreading to more critical systems.
4. Session Monitoring: Implement session duration limits and inactivity timeouts for third-party accounts to reduce the window of opportunity for an attacker using a hijacked session.