Cyber Threat Intelligence
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Ransomware Victim Education

Substitute Teacher Service

Ransomware attack by Cicada3301 Β· Disclosed February 9, 2025 Β· πŸ‡ΊπŸ‡Έ United States

thesubservice.com

Date Disclosed
Feb 9, 2025
2025
Threat Group
Cicada3301
75 total victims
Country
πŸ‡ΊπŸ‡Έ United States
Industry
Education

ThreatAI Analysis

Compiled from this incident record and the threat intelligence profile for Cicada3301. Figures and technique mappings are quoted from the source data, not inferred.

About the Cicada3301 group

Cicada3301 is a ransomware-as-a-service group (tracked as Repellent Scorpius by Palo Alto) that emerged in mid-2024 using Rust-based ransomware targeting Windows, Linux, and ESXi systems, suspected to be a successor of BlackCat/ALPHV and running an affiliate program with 20% commissions. Cicada3301 has listed 75 victims since June 2024.

Incident Analysis

Substitute Teacher Service was targeted by Cicada3301 ransomware, one of the most active ransomware groups in our database with 75 confirmed victims globally. The attack was disclosed on February 9, 2025, when Substitute Teacher Service appeared on the group's dark web leak site.

Substitute Teacher Service is based in United States , operating in the Education sector. United States ranks #1 globally for ransomware attacks, with 9,450 victims in our database.

Sector context: Educational institutions often have under-resourced IT security teams and hold large amounts of student and faculty personal data, making them attractive targets for ransomware groups.

Cicada3301 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 β€” 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 9, 2026 10:00 UTC.

Frequently Asked Questions

Was Substitute Teacher Service attacked by ransomware?

Yes. Substitute Teacher Service was listed as a victim of the Cicada3301 ransomware group on February 9, 2025. The organisation is based in United States and operates in the Education sector. The disclosure appeared on the group's dark web leak site.

Which ransomware group attacked Substitute Teacher Service?

Substitute Teacher Service was attacked by Cicada3301 ransomware. Cicada3301 is one of the most active ransomware groups, having claimed 75 victims globally. The group typically employs a double-extortion model: encrypting the victim's files and threatening to publish stolen data.

When did the Substitute Teacher Service ransomware attack occur?

The ransomware attack on Substitute Teacher Service was disclosed on February 9, 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 Substitute Teacher Service ransomware attack?

The specific data stolen from Substitute Teacher Service 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 Education organisation, Substitute Teacher Service likely held student and faculty personal data and academic records.

How can organisations protect against Cicada3301 attacks?

To defend against Cicada3301 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.