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Incident

Colliers International Group

Incident posture

Attack window
Nov 2020
Location
Canada
Status
Historical
CIA posture
Available to members
Updated
2025-10-28 00:00

Linked entities

Victim
Colliers International Group
Threat actors
1 actor
Sources
1 source

Timeline

Occurred
Nov 2020
Discovered
Pending
Disclosed
Pending
Resolved
Pending

Summary

Colliers International Group, a Toronto-based commercial real estate services firm, experienced a cyberattack potentially linked to the Netfilm ransomware gang, which listed stolen company files on the dark web as proof of data exfiltration. The organization acknowledged the security incident but declined to confirm whether ransomware was involved or validate the attackers' claims regarding compromised data.

Motives

Detailed motive labels are available to members.

1 motive

TTPs

Detailed technique labels are available to members.

1 technique

Description

Colliers International Group, a Toronto-based commercial real estate services firm, experienced a cyberattack in November 2020. The company publicly acknowledged the incident after being confronted by IT World Canada regarding evidence of the attack posted on the dark web. A ransomware group identified as "Netfilm" (likely a misspelling of NetWalker) claimed responsibility for the breach and listed Colliers' data on their dark web leak site, indicating they had successfully exfiltrated company files prior to encryption. The listing served as proof that attackers had accessed and copied sensitive information from Colliers' systems. Despite this public evidence of data theft, Colliers declined to confirm whether ransomware was involved in the incident when questioned by media outlets. The company spokesperson verified only that a cyberattack had occurred, without providing additional technical details about the intrusion vector, scope of compromised systems, or specific data types affected. The timing of the dark web listing relative to the November attack timeline suggests the threat actors operated undetected for a period before executing their ransomware payload and exfiltration efforts.

The attackers' publication of stolen data demonstrated successful network penetration and established that Colliers suffered a data breach beyond mere system encryption. The company's refusal to confirm the ransomware component contrasted with standard incident disclosure practices when faced with irrefutable evidence of data exfiltration. No details were released regarding containment measures, forensic investigations, or potential operational disruptions resulting from the attack. The absence of confirmed information about data types left stakeholders uncertain about potential exposure risks, though the ransomware group's typical targets included financial documents, client information, and corporate communications. Colliers did not disclose whether they engaged with the threat actors, paid any ransom demands, or implemented specific remediation steps following the attack. The incident highlighted ongoing challenges in corporate transparency regarding ransomware impacts, particularly when attackers publicly validate breach claims through data dumps.

Sources

Sources available to members: 1 source.

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