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Ransomware victim Education

katholiekamersfoort.nl

Listed by Stormous on · organisation based in Netherlands

katholiekamersfoort.nl

Disclosed
Jun 2, 2026
Leak-site listing date
Threat group
Stormous
110 victims listed
Country
Netherlands
#22 most targeted
Sector
Education

ThreatAI analysis

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

About the Stormous group

Stormous is an Arabic-speaking, pro-Russian ransomware and hacktivist group active since at least 2022, known for politically motivated attacks across 15+ countries, collaborating with GhostSec on the GhostLocker 2.0 RaaS platform and inheriting GhostSec's RaaS operations in mid-2024. On 1st July 2026 the group has annonced the end of their operations & ervices Stormous has listed 188 victims since March 2022.

How Stormous is documented to operate

Valid Accounts T1078 Stealth Persistence

Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Compromised credentials may be used to bypass access controls placed on various resources on systems within the network and may even be used for persistent access to remote systems and externally available services, such as VPNs, Outlook Web Access, network devices, and remote desktop. Compromised credentials may also grant an adversary increased privilege to specific systems or access to restricted areas of the network.

Mitigations: Application Developer Guidance, User Training, Password Policies, User Account Management, Privileged Account Management, Multi-factor Authentication

MITRE ATT&CK reference
Exploit Public-Facing Application T1190 Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network. The weakness in the system can be a software bug, a temporary glitch, or a misconfiguration. Exploited applications are often websites/web servers, but can also include databases (like SQL), standard services (like SMB or SSH), network device administration and management protocols (like SNMP and Smart Install), and any other system with Internet-accessible open sockets. On ESXi infrastructure, adversaries may exploit exposed OpenSLP services; they may alternatively exploit exposed VMware vCenter servers.

Mitigations: Vulnerability Scanning, Limit Access to Resource Over Network, Filter Network Traffic, Network Segmentation, Privileged Account Management, Application Isolation and Sandboxing

MITRE ATT&CK reference
Trusted Relationship T1199 Initial Access

Adversaries may breach or otherwise leverage organizations who have access to intended victims. Access through trusted third party relationship abuses an existing connection that may not be protected or receives less scrutiny than standard mechanisms of gaining access to a network. Organizations often grant elevated access to second or third-party external providers in order to allow them to manage internal systems as well as cloud-based environments. Some examples of these relationships include IT services contractors, managed security providers, infrastructure contractors (e.g. HVAC, elevators, physical security).

Mitigations: Network Segmentation, User Account Management, Multi-factor Authentication

MITRE ATT&CK reference
Phishing T1566 Initial Access

Adversaries may send phishing messages to gain access to victim systems. All forms of phishing are electronically delivered social engineering. Phishing can be targeted, known as spearphishing. In spearphishing, a specific individual, company, or industry will be targeted by the adversary. More generally, adversaries can conduct non-targeted phishing, such as in mass malware spam campaigns. Adversaries may send victims emails containing malicious attachments or links, typically to execute malicious code on victim systems. Phishing may also be conducted via third-party services, like social media platforms.

Mitigations: Network Intrusion Prevention, Restrict Web-Based Content, User Training, Antivirus/Antimalware, Software Configuration, Audit

MITRE ATT&CK reference
Command and Scripting Interpreter T1059 Execution

Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries. These interfaces and languages provide ways of interacting with computer systems and are a common feature across many different platforms. Most systems come with some built-in command-line interface and scripting capabilities, for example, macOS and Linux distributions include some flavor of Unix Shell while Windows installations include the Windows Command Shell and PowerShell. There are also cross-platform interpreters such as Python, as well as those commonly associated with client applications such as JavaScript and Visual Basic.

Mitigations: Restrict Web-Based Content, Limit Software Installation, Execution Prevention, Code Signing, Behavior Prevention on Endpoint, Privileged Account Management

MITRE ATT&CK reference

MITRE ATT&CK techniques attributed to Stormous across its recorded activity, not a finding about how katholiekamersfoort.nl was reached.

Incident analysis

katholiekamersfoort.nl was listed by Stormous ransomware, a group with 110 victims recorded in this database. The listing appeared on the group's leak site on June 2, 2026.

katholiekamersfoort.nl is based in Netherlands and operates in the Education sector. Netherlands ranks #22 worldwide for ransomware disclosures, with 147 victims in this 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.

Stormous typically follows a double extortion model: data is exfiltrated from the victim's systems before files are encrypted, so the victim faces two demands at once — pay to restore access, and pay to keep stolen data unpublished. The leak site, where this listing appeared, is the lever for the second demand.

Source. Public leak-site disclosures aggregated via the ransomware.live API. The disclosure date is when the listing was published, which can differ from the date of compromise. This site does not publish or link to stolen data. Last updated .

Frequently asked questions

Was katholiekamersfoort.nl attacked by ransomware?

Yes. katholiekamersfoort.nl was listed as a victim of the Stormous ransomware group on June 2, 2026. The organisation is based in Netherlands and operates in the Education sector. The disclosure appeared on the group's dark web leak site.

Which ransomware group attacked katholiekamersfoort.nl?

katholiekamersfoort.nl was attacked by Stormous ransomware. Stormous is one of the most active ransomware groups, having claimed 110 victims globally. The group typically employs a double-extortion model: encrypting the victim's files and threatening to publish stolen data.

When did the katholiekamersfoort.nl ransomware attack occur?

The ransomware attack on katholiekamersfoort.nl was disclosed on June 2, 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 katholiekamersfoort.nl ransomware attack?

The specific data stolen from katholiekamersfoort.nl 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, katholiekamersfoort.nl likely held student and faculty personal data and academic records.

How can organisations protect against Stormous attacks?

To defend against Stormous 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.