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Incident

Douglas Elliman

Incident posture

Attack window
Apr 2021
Location
United States of America
Status
Historical
CIA posture
Available to members
Updated
2025-10-25 00:00

Linked entities

Victim
Douglas Elliman
Threat actors
0 actors
Sources
1 source

Timeline

Occurred
Apr 2021
Discovered
Pending
Disclosed
Pending
Resolved
Pending

Summary

A property management division of Douglas Elliman experienced a cybersecurity breach involving unauthorized access to its IT network, potentially compromising personal information belonging to residents and employees across numerous New York cooperative and condominium buildings. The incident, detected through suspicious system activity, prompted notifications to hundreds of affiliated building boards regarding the exposure of sensitive data maintained within the compromised network.

Motives

Detailed motive labels are available to members.

1 motive

TTPs

Detailed technique labels are available to members.

1 technique

Description

On April 7, 2021, Douglas Elliman Property Management detected suspicious activity on its IT network, prompting an investigation into a potential security breach. The incident compromised systems containing personal information belonging to residents of New York cooperative and condominium buildings managed by the firm, as well as employee data. Within the same month, the company's three managing directors notified hundreds of affiliated property boards via email about the breach and the potential exposure of sensitive information. The internal communication confirmed unauthorized access to the IT infrastructure but did not specify the duration of the threat actor's presence in the network prior to detection. No technical details about the attack vector or methods of intrusion were disclosed in the initial advisory.

The breach placed thousands of New York residents at risk of personal data exposure, though the notification did not enumerate the exact number of affected individuals or specify which data categories were accessed. Douglas Elliman Property Management’s response focused on informing stakeholders through direct communication with building governing boards rather than issuing public statements. The company did not initially disclose whether law enforcement was engaged or whether third-party cybersecurity firms assisted in the investigation. No evidence of data misuse was reported at the time of notification, and the firm did not announce remediation offers such as credit monitoring for impacted parties. The incident highlighted operational vulnerabilities in property management IT systems handling resident and employee information.

Sources

Sources available to members: 1 source.

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