The threat described pertains to a variant of the Locky ransomware identified around September 6, 2017, distributed via messages mimicking voice message notifications from an unknown phone number (e.g., "Voice Message from 011234567890 - name unavailable"). The attack vector involves social engineering through phishing messages containing links to a /message.html page, which likely hosts malicious payloads. Upon interaction, the malware would execute and encrypt user files, demanding ransom payments for decryption. Locky ransomware is known for its widespread impact and use of strong encryption algorithms, making recovery without backups difficult. This particular variant is categorized as low severity in the provided data, possibly due to limited distribution or reduced impact compared to other Locky campaigns. No specific affected software versions or exploits are listed, indicating that the infection vector relies primarily on user interaction with phishing content rather than exploiting software vulnerabilities. The absence of known exploits in the wild and lack of patch information further supports this. The technical details indicate a moderate threat level (3) and minimal analysis depth (1), suggesting limited available intelligence on this variant. Overall, this is a classic ransomware campaign leveraging social engineering to trick users into executing malicious code.

For European organizations, the impact of this Locky ransomware variant can range from data loss to operational disruption. If users fall victim to the phishing messages and execute the malicious payload, critical files could be encrypted, leading to downtime and potential financial losses if backups are inadequate or recovery is delayed. Given the ransomware nature, confidentiality is compromised as attackers gain control over data availability. While the severity is noted as low, organizations with less mature security awareness or lacking robust email filtering may be more vulnerable. The campaign's reliance on social engineering means that sectors with high email communication volumes, such as finance, healthcare, and public administration, could face increased risk. Additionally, organizations without effective incident response plans or offline backups may suffer prolonged outages. However, since no known exploits or automated infection vectors are reported, the threat requires user interaction, somewhat limiting its spread and impact.

To mitigate this threat, European organizations should implement targeted measures beyond generic advice: 1) Enhance email security by deploying advanced phishing detection tools that analyze message content and URLs, specifically flagging messages purporting to be voice message notifications. 2) Conduct focused user awareness training emphasizing the risks of interacting with unsolicited messages containing links, especially those claiming to be voice messages or from unknown numbers. 3) Implement strict URL filtering and sandboxing to analyze suspicious links before user access. 4) Maintain robust, tested offline backups to ensure rapid recovery without paying ransom. 5) Employ endpoint detection and response (EDR) solutions capable of identifying ransomware behaviors early, such as rapid file encryption. 6) Monitor network traffic for unusual activity indicative of ransomware communication with command and control servers. 7) Establish incident response procedures tailored to ransomware events, including isolation protocols to prevent lateral movement. These steps, combined with regular patching of all systems (even if no direct exploit is known), will reduce the likelihood and impact of infection.