Cyber Threat Intelligence
CTI Academy Sponsor CTI Academy
AS
Ransomware Victim Technology

Ascom Holding AG

Ransomware attack by Hellcat · Disclosed March 16, 2025 · 🇨🇭 Switzerland

ascom.com

Date Disclosed
Mar 16, 2025
2025
Threat Group
Hellcat
20 total victims
Country
🇨🇭 Switzerland
Industry
Technology

ThreatAI Analysis

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

About the Hellcat group

HellCat is a ransomware-as-a-service group that formed in Q4 2024 and quickly became notable for high-profile attacks against Schneider Electric, Telefónica, and Israel's Knesset, primarily gaining initial access via stolen Jira credentials harvested by infostealer malware, targeting critical infrastructure and government entities. Hellcat has listed 20 victims since October 2024.

Incident Analysis

Ascom Holding AG was targeted by Hellcat ransomware, one of the most active ransomware groups in our database with 20 confirmed victims globally. The attack was disclosed on March 16, 2025, when Ascom Holding AG appeared on the group's dark web leak site.

Ascom Holding AG is based in Switzerland , operating in the Technology sector. Switzerland ranks #13 globally for ransomware attacks, with 194 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.

Hellcat 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 20:00 UTC.

Frequently Asked Questions

Was Ascom Holding AG attacked by ransomware?

Yes. Ascom Holding AG was listed as a victim of the Hellcat ransomware group on March 16, 2025. The organisation is based in Switzerland and operates in the Technology sector. The disclosure appeared on the group's dark web leak site.

Which ransomware group attacked Ascom Holding AG?

Ascom Holding AG was attacked by Hellcat ransomware. Hellcat is one of the most active ransomware groups, having claimed 20 victims globally. The group typically employs a double-extortion model: encrypting the victim's files and threatening to publish stolen data.

When did the Ascom Holding AG ransomware attack occur?

The ransomware attack on Ascom Holding AG was disclosed on March 16, 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 Ascom Holding AG ransomware attack?

The specific data stolen from Ascom Holding AG 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, Ascom Holding AG likely held source code, intellectual property, and customer data.

How can organisations protect against Hellcat attacks?

To defend against Hellcat 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.