A new wave of Emotet malware campaign distribute the Nozelesn ransomware that targets hospitality industries based endpoint systems via malicious word documents.
Telemetry had over 14,000 detections via emotet spam emails that are distributed all over the world between January 9, 2019, and February 7, 2019.
These mass infections mainly targeting specific countries including
Great Britain, Cyprus, Germany, Argentina, Canada and several locations in a different time period.
Initially, this new campaign uncovered via Trend Micro’s managed detection and response (MDR) monitoring system where researchers able to discover nearly 580 similar Emotet file attachment samples.
Attackers using most common social engineering techniques in email such as “latest invoice,” “shipping details,” “wire sent out today,” and “urgent delivery to compromise victims to click the link or open the attached malicious documents.
In this case, spam emails contain an attached word document once the attachment is opened, a macro executes then eventually calls PowerShell to download another malware from a remote server.
In this case, spam emails contain an attached word document Once the attachment is opened, a macro executes then eventually calls PowerShell to download another malware from a remote server.
Emotet Malware Infection Process
During the investigation process, researchers discovered a suspicious file called “How_Fix_Nozelesn_files.htm” in the endpoint (server) where they were also find an indication of a Nozelesn ransomware infection.
Further root cause chain analysis revealed that the malicious document file was opened in Microsoft Word and was downloaded via Google Chrome.
Once the victims open the file, PowerShell.exe executes to connect with several IP address and create another file 942.exe.
According to Trend Micro analysis, “Based on its behavior, the malware may have been connecting to multiple IP addresses to download another malware which it will execute in the system. In this case, we noticed that it was also continuously downloading an update of itself, contacting a new set of command-and-control (C&C) servers each time.”
Later it drops the secondary payload which is very similar to with Nymaim that is linked with Nozelesn ransomware.
Finally, Nymaim loaded the Nozelesn ransomware into the infected system then encrypted files in the endpoint system (server) via shared folders.