The RIG exploit kit is a widely known toolkit used by threat actors to deliver various types of malware by exploiting vulnerabilities in browsers and their plugins. In this case, the RIG exploit kit has been observed distributing the Princess ransomware, also known as Princess Locker. Princess ransomware is a type of malicious software that encrypts victims' files and demands a ransom payment to restore access. The distribution method involves the RIG exploit kit scanning for vulnerable systems, typically through drive-by downloads on compromised or malicious websites, and then deploying the ransomware payload without user consent or interaction. Although the specific affected versions or vulnerabilities exploited by the RIG kit in this campaign are not detailed, historically, RIG targets vulnerabilities in Adobe Flash, Internet Explorer, and other common browser components. The Princess ransomware encrypts files and appends a unique extension, locking users out of their data. Victims are presented with ransom notes demanding payment, often in cryptocurrency, to receive decryption keys. The threat level is considered low in this report, possibly due to limited distribution or impact observed at the time. However, ransomware remains a significant threat due to its potential to disrupt business operations and cause data loss. The lack of known exploits in the wild at the time of reporting suggests this was an emerging or limited campaign. The technical details indicate a moderate threat level and analysis confidence, but no specific technical indicators or patches are provided.

For European organizations, the impact of the RIG exploit kit distributing Princess ransomware can be considerable despite the low severity rating in the original report. Ransomware can lead to significant operational disruption, data loss, and financial costs related to ransom payments, recovery efforts, and reputational damage. Organizations with inadequate patch management or outdated browser components are particularly vulnerable. The indirect impact includes potential regulatory fines under GDPR if personal data is compromised or lost. Sectors such as healthcare, finance, and critical infrastructure in Europe are especially at risk due to their reliance on continuous data availability and stringent data protection requirements. The stealthy nature of exploit kits like RIG means infections can occur without user interaction, increasing the risk of widespread compromise before detection. Although this specific campaign was noted in 2017, the tactics remain relevant as exploit kits and ransomware continue to evolve. European organizations must consider the threat from exploit kits as part of their broader ransomware defense strategy.

To mitigate the threat posed by the RIG exploit kit and Princess ransomware, European organizations should implement a multi-layered security approach. First, ensure all systems, especially browsers and plugins like Adobe Flash and Java, are fully patched and updated to close known vulnerabilities exploited by RIG. Disable or remove unnecessary browser plugins to reduce the attack surface. Employ network-level protections such as web filtering and intrusion prevention systems to block access to known exploit kit domains and malicious payload delivery sites. Use endpoint detection and response (EDR) solutions capable of identifying exploit kit behaviors and ransomware activity. Regularly back up critical data with offline or immutable backups to enable recovery without paying ransom. Conduct user awareness training focused on recognizing suspicious websites and phishing attempts that may lead to exploit kit exposure. Implement application whitelisting to prevent unauthorized execution of ransomware binaries. Finally, maintain an incident response plan specifically addressing ransomware incidents to minimize downtime and data loss.