Trojan.W97M.EMOTET.TIOIBEMZ

 Analysis by: Denisse Camille Layco

 ALIASES:

TrojanDownloader:O97M/Emotet.CSK!MTB (MICROSOFT); W97M/Downloader.dif (NAI)

 PLATFORM:

Windows

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW


This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

  TECHNICAL DETAILS

File Size:

218,460 bytes

File Type:

DOC

Initial Samples Received Date:

23 Dec 2020

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan drops the following files:

  • %User Profile%\O_wgqv7\C0316em\Lyeta6ud.dll -> deleted later
  • When ran with administrator privileges:
    • %System%\{random characters}\{random characters}.{random characters}
  • When ran without administrator privileges:
    • %AppDataLocal%\{random characters}\{random characters}.{random characters}

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name} on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following processes:

  • %System%\wbem\wmiprvse.exe -secured -Embedding
  • cmd cmd cmd cmd /c msg %username% /v Word experienced an error trying to open the file. & POwersheLL -w hidden -ENCOD {Base64 encoded string}
  • "%System%\rundll32.exe" %User Profile%\O_wgqv7\C0316em\Lyeta6ud.dll #1
  • When ran with administrator privileges:
    • %System%\rundll32.exe "%System%\{random characters}\{random characters}.{random characters}",RunDLL
  • When ran without administrator privileges:
    • %System%\rundll32.exe "%AppDataLocal%\{random characters}\{random characters}.{random characters}",RunDLL

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name} on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It creates the following folders:

  • %User Profile%\O_wgqv7
  • %User Profile%\O_wgqv7\C0316em
  • When ran with administrator privileges:
    • %System%\{random characters}
  • When ran without administrator privileges:
    • %AppDataLocal%\{random characters}

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name} on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}campus.com/l/yQ/
  • http://apps.{BLOCKED}ust.com/roots/dstrootcax3.p7c
  • http://{BLOCKED}rdableroofer.com/ralphs-receipt-f2uhf/qTT5DC/
  • http://{BLOCKED}ileged.com/cgi-bin/kcggF/
  • http://{BLOCKED}.{BLOCKED}.209.15/{random characters}/
  • http://{BLOCKED}.{BLOCKED}.237.56:8080/{random characters}
  • http://{BLOCKED}.{BLOCKED}.148.58:443/{random characters}