jastrebarsko.hr Listed by threeam Ransomware Group: Ransomware Claim — What’s Alleged & What To Do
jastrebarsko.hr has been listed by the threeam Ransomware Group, with internal files reported as exfiltrated in the attack. The listing was disclosed on June 12, 2026; an undisclosed number of people may be affected, and anyone connected to the organisation should check whether their data has been exposed and take appropriate steps.
Breaking down the breach
The incident involves the municipal domain jastrebarsko.hr, which belongs to the Town of Jastrebarsko, a historic city in Central Croatia situated between Zagreb and Karlovac. Public reporting indicates only that the threeam group listed the domain and asserted that internal files had been taken. No details on the timing of the intrusion, the volume of data, the method of access, or any ransom demand have been disclosed. The number of people affected is recorded as unknown.
The group behind it: threeam
Threeam is a ransomware operation that maintains a leak site where it lists organizations it claims to have compromised. The group typically follows a double-extortion pattern, first copying data and later encrypting systems, then using the threat of publication to pressure victims. Its listings appear on a dedicated site and are presented as claims by the group rather than independently verified events. In this case, the group claims responsibility for the jastrebarsko.hr intrusion through its listing, but no additional statements or evidence from threeam about this specific target have been made public.
About jastrebarsko.hr
Jastrebarsko.hr serves as the official online presence of the Town of Jastrebarsko, a municipality responsible for local government services in central Croatia. Such municipal sites commonly manage administrative records, citizen registrations, local tax information, and communications related to public services. A breach at this level can involve data tied to residents' interactions with local authorities, though the exact scope of systems connected to the domain remains undisclosed.
What was likely exposed
The only detail released is that internal files were allegedly exfiltrated. No inventory of file types, databases, or specific data categories has been published. Municipal organizations of this kind routinely hold records such as resident identification details, property information, correspondence, and operational documents. Because the precise contents have not been confirmed, it is not possible to state which categories, if any, were taken.
Why it matters
Municipal data often includes information that individuals cannot easily change, such as addresses, identification numbers, or records of local services. Exposure of such material can lead to targeted fraud, misuse in identity-related schemes, or unwanted disclosure of personal circumstances. For the town administration, the incident raises questions about the security of systems that support public services, though the operational impact has not been detailed in available reports.
What to do if you're exposed
Residents of Jastrebarsko who are concerned about possible exposure should monitor their financial accounts and official correspondence for unusual activity. Enabling multi-factor authentication on any accounts linked to the municipality and reviewing privacy settings on government portals are standard first steps. Individuals can also run a free exposure scan of their email address against known breach data to check for appearances in previously published records.
AICompiled with AI assistance from public sources and published under our editorial standards.
How this breach connects
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Publicly posted by threeam — unverified claim, pending independent verification
Breach listings — particularly those originating from ransomware or leak sites — are third-party claims that may be unverified, incomplete, or inaccurate. A listing does not by itself confirm that a breach occurred or that any specific data was exposed. Severity is an automated assessment, not a definitive rating. Verification status is shown where available.
Attributions to threat groups and methods reflect public reporting and, in some cases, unverified claims made by the groups themselves; they may be incomplete or later revised. Recent Breaches and GalaxyWarden are independent and are not affiliated with, and do not endorse, any company or group named on this page. This information is aggregated from public sources for awareness only and is not legal, security, or investment advice.