Researchers discovered the spread of a malicious exe file that targets specific individuals and is disguised as information related to a personal data leak.
The malware functions as a backdoor, executing obfuscated commands in XML format after receiving them from the threat actor.
Because this malware is focused on specific targets, users should avoid opening attachments in emails from unknown senders.
Malicious exe File Disguised as a Word File
According to the AhnLab Security Emergency Response Center (ASEC), an email purporting to be from a cyber investigation team was sent. Furthermore, the infected exe file was pretended to be a Word document.
“When the malicious exe file is executed, the files in the .data section are created into the %Programdata% folder. Out of the created files, all files are obfuscated except for the legitimate doc file”, ASEC said in a report shared with Cyber Security News.
Except for the legitimate doc file, every file that was generated is obfuscated as given below:
- Lomd02.png (Malicious jse script)
- Operator.jse (Malicious jse script)
- WindowsHotfixUpdate.jse (Malicious jse script)
- 20231126_9680259278.doc (Legitimate doc file)
- WindowsHotfixUpdate.ps1 (Malicious PowerShell script)
Researchers said among the newly generated files is a valid document file called ‘20231126_9680259278.doc’. This was most likely included by the threat actor to trick the user into thinking they had opened a legitimate file.
Because the C2 was closed in this case, the malware’s ultimate action was not visible; however, researchers say it functions as a backdoor by receiving obfuscated commands from the threat actor and executing them in XML format.
In this scenario, normal users are unable to detect that their PCs are infected with malware because the bait file is executed concurrently.
Hence, individuals should avoid opening attachments from emails they receive from unidentified sources since these malicious files are meant to target individual people.