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Ransomware Victim Construction

Westrian Group

Ransomware attack by Interlock · Disclosed November 24, 2025 · 🇺🇸 United States

jrengineering.com

Date Disclosed
Nov 24, 2025
2025
Threat Group
Interlock
125 total victims
Country
🇺🇸 United States
Industry
Construction

ThreatAI Analysis

Compiled from this incident record and the threat intelligence profile for Interlock. Figures and technique mappings are quoted from the source data, not inferred.

About the Interlock group

Interlock is a ransomware group first observed in September 2024 that targets critical infrastructure sectors including healthcare, government, education, and technology across North America and Europe using double-extortion, with 57+ claimed victims including a major US dialysis provider exposing over two million patient records. Interlock has listed 119 victims since December 2023.

Incident Analysis

Westrian Group was targeted by Interlock ransomware, one of the most active ransomware groups in our database with 125 confirmed victims globally. The attack was disclosed on November 24, 2025, when Westrian Group appeared on the group's dark web leak site.

Westrian Group is based in United States , operating in the Construction sector. United States ranks #1 globally for ransomware attacks, with 9,415 victims in our database.

Sector context: Construction firms often hold sensitive project data, client financials, and intellectual property. The industry's typically lean IT security teams can make them more vulnerable.

Interlock typically employs a double extortion model: first exfiltrating sensitive data from the victim's systems, then deploying ransomware to encrypt files. Victims face two simultaneous threats — paying to restore access and paying to prevent publication of stolen data. The group's leak site publishes victim names and exfiltrated data as leverage.

Data source: This incident record is sourced from public ransomware group leak site disclosures aggregated via the ransomware.live API. Disclosure date reflects when the victim was published on the leak site, which may differ from the initial date of compromise. This platform does not publish or link to stolen data. Last data update: Sep 5, 2026 16:00 UTC.

Frequently Asked Questions

Was Westrian Group attacked by ransomware?

Yes. Westrian Group was listed as a victim of the Interlock ransomware group on November 24, 2025. The organisation is based in United States and operates in the Construction sector. The disclosure appeared on the group's dark web leak site.

Which ransomware group attacked Westrian Group?

Westrian Group was attacked by Interlock ransomware. Interlock is one of the most active ransomware groups, having claimed 125 victims globally. The group typically employs a double-extortion model: encrypting the victim's files and threatening to publish stolen data.

When did the Westrian Group ransomware attack occur?

The ransomware attack on Westrian Group was disclosed on November 24, 2025. This date reflects when the victim was published on the threat group's leak site, which may differ from the actual date of initial compromise.

What data was stolen in the Westrian Group ransomware attack?

The specific data stolen from Westrian Group has not been independently verified by this platform. Ransomware groups typically exfiltrate data before encrypting systems and use the threat of publication to pressure victims. As a Construction organisation, Westrian Group likely held sensitive business data, client information, and operational records.

How can organisations protect against Interlock attacks?

To defend against Interlock and similar threat actors, organisations should: maintain regular offline backups tested for restoration; implement network segmentation to limit lateral movement; deploy multi-factor authentication on all remote access; use endpoint detection and response (EDR) tools; conduct regular phishing and security awareness training; and monitor threat intelligence feeds for indicators of compromise (IOCs) associated with active groups.