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Ransomware Victim Technology

AT&T

Ransomware attack by Endzone · Disclosed September 18, 2026 · 🇺🇸 United States

att.com

Date Disclosed
Sep 18, 2026
2026
Threat Group
Endzone
2 total victims
Country
🇺🇸 United States
Industry
Technology

ThreatAI Analysis

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

Endzone listed AT&T on its dark web leak site on 18 September 2026. AT&T is based in United States and operates in the Technology sector.

About the Endzone group

Endzone has listed 2 victims since September 2026.

Incident Analysis

AT&T was targeted by Endzone ransomware, one of the most active ransomware groups in our database with 2 confirmed victims globally. The attack was disclosed on September 18, 2026, when AT&T appeared on the group's dark web leak site.

AT&T is based in United States , operating in the Technology sector. United States ranks #1 globally for ransomware attacks, with 9,526 victims in our database.

Sector context: Technology companies hold intellectual property, customer data, and source code — all highly valuable assets. A successful ransomware attack can also put downstream customers at risk through supply chain exposure.

Endzone 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 18, 2026 14:00 UTC.

Frequently Asked Questions

Was AT&T attacked by ransomware?

Yes. AT&T was listed as a victim of the Endzone ransomware group on September 18, 2026. The organisation is based in United States and operates in the Technology sector. The disclosure appeared on the group's dark web leak site.

Which ransomware group attacked AT&T?

AT&T was attacked by Endzone ransomware. Endzone is one of the most active ransomware groups, having claimed 2 victims globally. The group typically employs a double-extortion model: encrypting the victim's files and threatening to publish stolen data.

When did the AT&T ransomware attack occur?

The ransomware attack on AT&T was disclosed on September 18, 2026. 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 AT&T ransomware attack?

The specific data stolen from AT&T 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 Technology organisation, AT&T likely held source code, intellectual property, and customer data.

How can organisations protect against Endzone attacks?

To defend against Endzone 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.