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Ransomware Victim Public Sector

Region of Istria

Ransomware attack by Qilin ยท Disclosed December 15, 2025 ยท ๐Ÿ‡ญ๐Ÿ‡ท Croatia

www.istra-istria.hr

Date Disclosed
Dec 15, 2025
2025
Threat Group
Qilin
2,075 total victims
Country
๐Ÿ‡ญ๐Ÿ‡ท Croatia
Industry
Public Sector

Incident Analysis

Region of Istria was targeted by Qilin ransomware, one of the most active ransomware groups in our database with 2,075 confirmed victims globally. The attack was disclosed on December 15, 2025, when Region of Istria appeared on the group's dark web leak site.

Region of Istria is based in Croatia , operating in the Public Sector sector. Croatia ranks #51 globally for ransomware attacks, with 26 victims in our database.

Sector context: Organisations in this sector hold valuable data and operational systems that ransomware groups seek to exploit for financial gain through encryption and data exfiltration.

Qilin 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 โ€” 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: Aug 5, 2026 04:00 UTC.

Frequently Asked Questions

Was Region of Istria attacked by ransomware?

Yes. Region of Istria was listed as a victim of the Qilin ransomware group on December 15, 2025. The organisation is based in Croatia and operates in the Public Sector sector. The disclosure appeared on the group's dark web leak site.

Which ransomware group attacked Region of Istria?

Region of Istria was attacked by Qilin ransomware. Qilin is one of the most active ransomware groups, having claimed 2,075 victims globally. The group typically employs a double-extortion model: encrypting the victim's files and threatening to publish stolen data.

When did the Region of Istria ransomware attack occur?

The ransomware attack on Region of Istria was disclosed on December 15, 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 Region of Istria ransomware attack?

The specific data stolen from Region of Istria 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 Public Sector organisation, Region of Istria likely held sensitive business data, client information, and operational records.

How can organisations protect against Qilin attacks?

To defend against Qilin 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.