This threat report describes a malware campaign involving the Locky ransomware and TrickBot malware, identified around October 18, 2017. Locky is a well-known ransomware family that encrypts victim files and demands payment for decryption keys. TrickBot is a modular banking Trojan and malware loader often used to distribute ransomware like Locky. The specific sample referenced appears to be delivered via a malicious archive file named "Invoice 123456789 10.18.2017.7z", which likely contains a payload with the Locky ransomware and TrickBot components. The mention of "M2M" and "Locky Affid=3, '.asasin'/Trickbot 'mac1'" suggests a particular variant or campaign identifier used by the reporting entity (CIRCL). The infection vector is presumably phishing emails with malicious attachments disguised as invoices, a common tactic for these malware families. Once executed, TrickBot may establish persistence, steal credentials, and download Locky ransomware to encrypt files. The report classifies the severity as low and indicates no known exploits in the wild beyond the malware's standard infection methods. The technical details show a moderate threat level (3) and limited analysis depth (1), reflecting a known but not highly sophisticated or novel threat. No affected product versions or patches are listed, as this is malware rather than a software vulnerability. Overall, this is a typical ransomware campaign leveraging TrickBot as a delivery mechanism, targeting users through social engineering and malicious attachments to cause data encryption and potential financial loss.

For European organizations, the impact of this threat can vary but generally includes disruption of business operations due to encrypted data, potential financial losses from ransom payments or recovery costs, and reputational damage. Locky ransomware can encrypt a wide range of file types, potentially affecting critical business data and systems. TrickBot's credential theft capabilities may lead to further compromise, including unauthorized access to sensitive systems or data breaches. European entities with less mature cybersecurity defenses or insufficient email filtering are particularly at risk. The low severity rating suggests that while the threat is real, it may be mitigated by standard security controls and user awareness. However, organizations in sectors with high-value data or critical infrastructure could face more severe consequences if infected. Additionally, the use of phishing emails as the infection vector means that human factors play a significant role in the threat's success, emphasizing the need for user training and robust email security.

To mitigate this threat effectively, European organizations should implement targeted measures beyond generic advice: 1) Deploy advanced email filtering solutions capable of detecting and quarantining malicious attachments, especially compressed archives like .7z files with suspicious naming patterns. 2) Conduct regular, scenario-based phishing awareness training to help users recognize and report suspicious emails, focusing on invoice-themed lures. 3) Implement application whitelisting and restrict execution of unauthorized scripts or executables, particularly from temporary or user download folders. 4) Maintain up-to-date endpoint detection and response (EDR) tools that can identify TrickBot behaviors such as credential harvesting and lateral movement attempts. 5) Regularly back up critical data with offline or immutable backups to enable recovery without paying ransom. 6) Monitor network traffic for indicators of TrickBot command and control communications and isolate infected hosts promptly. 7) Enforce least privilege principles and multi-factor authentication to limit the impact of credential theft. These focused controls can significantly reduce the risk and impact of Locky and TrickBot infections.