This threat relates to a malware campaign involving the Locky ransomware and the Trickbot banking Trojan, identified around October 11, 2017. The Locky ransomware is known for encrypting victims' files and demanding ransom payments, often delivered via malicious email attachments or links. The Trickbot Trojan is a modular malware primarily used for stealing banking credentials and facilitating further malware infections. The reference to "M2M - Locky Affid=3, '.asasin'/Trickbot 'mac1'" suggests a combined or sequential use of these malware families, potentially indicating a multi-stage attack where Trickbot is used to gain initial access or steal credentials, followed by Locky ransomware deployment to encrypt data. The mention of filenames like "Supplement payment 1234567890" and "F1234567890_11102017.7z" implies the use of socially engineered email lures mimicking payment or invoice documents, a common tactic to entice victims to open malicious attachments. The ransomware likely encrypts files with extensions such as ".asasin" or similar, consistent with Locky's behavior of changing file extensions post-encryption. Although the severity is marked as low and no known exploits in the wild are indicated, the presence of these malware families in combination represents a persistent threat vector. The lack of affected versions and patch links suggests this is a malware campaign rather than a software vulnerability. The threat level of 3 and analysis score of 1 indicate moderate concern but limited detailed technical information is available in this report.

For European organizations, this threat can lead to significant operational disruption and financial loss. Locky ransomware encrypts critical files, potentially halting business processes until a ransom is paid or data is restored from backups. Trickbot's credential theft capabilities can lead to unauthorized access to banking and corporate accounts, increasing the risk of fraud and further compromise. The use of payment-themed social engineering lures targets finance departments, which are common across all sectors, increasing the attack surface. Even though the severity is low in this report, the combined use of Trickbot and Locky has historically resulted in impactful incidents. European organizations with inadequate email filtering, endpoint protection, or user awareness are particularly vulnerable. The threat also poses risks to data confidentiality and integrity, as stolen credentials can be used for lateral movement or data exfiltration. Recovery costs, reputational damage, and potential regulatory penalties under GDPR for data breaches add to the impact.

European organizations should implement advanced email filtering solutions to detect and quarantine suspicious attachments, especially those using archive formats like .7z. Endpoint detection and response (EDR) tools should be deployed to identify and block Trickbot and Locky behaviors, including unusual file encryption activities and credential theft attempts. Regular user training focused on recognizing phishing emails with payment or invoice themes is critical. Network segmentation can limit lateral movement if Trickbot gains access. Organizations should maintain up-to-date backups stored offline or in immutable storage to enable recovery without paying ransom. Multi-factor authentication (MFA) should be enforced on all critical systems and banking portals to mitigate credential theft risks. Incident response plans must include procedures for ransomware events and credential compromise. Monitoring for known indicators of compromise related to Trickbot and Locky, even if none are provided here, is advisable using threat intelligence feeds. Finally, organizations should apply security patches promptly to reduce attack surface, even though no specific vulnerabilities are noted in this campaign.