The April 2025 Threat Trend Report on Ransomware provides a detailed statistical analysis of ransomware activity observed during April 2025, highlighting a relative increase in new ransomware samples compared to the previous month. The report aggregates data collected over a six-month period via the ATIP infrastructure, which includes the collection of MD5 hashes for some ransomware samples. It focuses on the evolving ransomware landscape by tracking various ransomware groups and the companies they have targeted, leveraging information from dedicated leak sites where victim data is often published. While the report does not specify particular ransomware variants or vulnerabilities exploited, it offers valuable insights into the volume and diversity of ransomware threats, emphasizing the persistent and growing nature of ransomware attacks globally, including within Korea and internationally. The absence of known exploits in the wild suggests that the report is more focused on trend analysis and sample collection rather than newly discovered zero-day vulnerabilities. The use of dedicated leak sites as a data source underscores the continued tactic of ransomware operators to publicly pressure victims into paying ransoms. Overall, the report serves as a comprehensive resource for understanding ransomware trends, sample proliferation, and victimology, which can inform defensive strategies and threat intelligence efforts.

For European organizations, the increasing volume of ransomware samples and the diversity of targeted companies indicate a sustained and potentially growing threat. Ransomware attacks can lead to significant operational disruption, data loss, financial costs from ransom payments or recovery efforts, reputational damage, and regulatory penalties, especially under GDPR for data breaches. The report's indication of a rise in new samples suggests that ransomware groups are actively evolving their tactics, techniques, and procedures (TTPs), which may include targeting critical infrastructure, healthcare, finance, and manufacturing sectors prevalent in Europe. The use of dedicated leak sites to publish victim data increases the risk of data exposure and extortion pressure. Given the international scope of the report, European entities are likely to be among the targets, particularly those with high-value data or critical services. The lack of specific affected versions or known exploits implies that the threat is broad-based, affecting multiple systems and relying on common ransomware delivery methods such as phishing, exploitation of unpatched vulnerabilities, or credential compromise. Consequently, European organizations face a medium-level risk of ransomware incidents that could impact confidentiality, integrity, and availability of their systems and data.

European organizations should implement targeted mitigation strategies beyond generic advice: 1) Enhance threat intelligence sharing by integrating data from sources like the ATIP infrastructure and monitoring dedicated leak sites to identify emerging ransomware groups and campaigns relevant to their sector and region. 2) Conduct regular, focused phishing simulation and user awareness training tailored to the latest ransomware delivery tactics observed in recent samples. 3) Prioritize patch management for vulnerabilities commonly exploited in ransomware attacks, even though no specific CVEs are mentioned, by maintaining up-to-date asset inventories and vulnerability assessments. 4) Implement robust network segmentation and least privilege access controls to limit lateral movement in case of compromise. 5) Deploy advanced endpoint detection and response (EDR) solutions capable of detecting ransomware behaviors, including file encryption activities and suspicious process executions. 6) Maintain and regularly test offline, immutable backups to ensure rapid recovery without paying ransoms. 7) Establish incident response plans that incorporate ransomware-specific scenarios and coordinate with law enforcement and cybersecurity agencies. 8) Monitor for indicators of compromise (IoCs) such as MD5 hashes from the report to proactively detect infections. These measures, combined with continuous monitoring and threat hunting, will enhance resilience against the evolving ransomware threat landscape described in the report.