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Ransomware Victim Construction

southweststone.net

Ransomware attack by J · Disclosed August 20, 2025 · 🇺🇸 United States

southweststone.net

Date Disclosed
Aug 20, 2025
2025
Threat Group
J
41 total victims
Country
🇺🇸 United States
Industry
Construction

ThreatAI Analysis

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

About the J group

J is an emerging ransomware group that launched its leak site in May 2025, claiming over 41 victims by late 2025 including FAI Aviation Group (Germany), operating primarily as a leak-site-centric extortion identity with limited public technical analysis. J has listed 41 victims since February 2025.

Incident Analysis

southweststone.net was targeted by J ransomware, one of the most active ransomware groups in our database with 41 confirmed victims globally. The attack was disclosed on August 20, 2025, when southweststone.net appeared on the group's dark web leak site.

southweststone.net is based in United States , operating in the Construction sector. United States ranks #1 globally for ransomware attacks, with 9,428 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.

J 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 7, 2026 04:00 UTC.

Frequently Asked Questions

Was southweststone.net attacked by ransomware?

Yes. southweststone.net was listed as a victim of the J ransomware group on August 20, 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 southweststone.net?

southweststone.net was attacked by J ransomware. J is one of the most active ransomware groups, having claimed 41 victims globally. The group typically employs a double-extortion model: encrypting the victim's files and threatening to publish stolen data.

When did the southweststone.net ransomware attack occur?

The ransomware attack on southweststone.net was disclosed on August 20, 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 southweststone.net ransomware attack?

The specific data stolen from southweststone.net 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, southweststone.net likely held sensitive business data, client information, and operational records.

How can organisations protect against J attacks?

To defend against J 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.