Modified by: Jay Bradley Nebre
 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet, Dropped by other malware

This AutoIt-compiled malware downloads a coinminer in affected systems. This malware is distributed by cybercriminals by bundling it with a legitimate installer of the Zoom communication app.

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: 19,645,440 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 31 Mar 2020
Payload: Connects to URLs/IPs, Steals information, Collects system information

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 adds the following processes:

  • %User Temp%\CL_Debug_Log.txt e -p"JDQJndnqwdnqw2139dn21n3b312idDQDB" "%User Temp%\CR_Debug_Log.txt" -o"%User Temp%\"
  • C:\Windows\system32\cmd.exe /c schtasks.exe /Create /XML "%User Temp%\SystemCheck.xml" /TN "System\SystemCheck"

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\asacpiex.dll -> archive file containing Coinminer.Win64.MOOZ.THCCABO
  • %User Temp%\CL_Debug_Log.txt -> 7-zip Archiver
  • %User Temp%\ZoomInstaller.exe -> normal Zoom Installer
  • %User Temp%\CR_Debug_Log.txt -> archive file containing Coinminer.Win64.MOOZ.THCCABO
  • %Application Data%\Microsoft\Windows\Helper.exe -> detected as Coinminer.Win64.MOOZ.THCCABO
  • %User Temp%\SystemCheck.xml

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

Information Theft

This Trojan gathers the following data:

  • System Information
  • OS Version
  • Video Controller
  • Processors
  • AV product
  • Smartscreen
  • Windows Defender

Other Details

This Trojan does the following:

  • It sends the gathered information to the following URL:
    • https://{BLOCKED}o.co/1IRnc

It adds the following scheduled tasks:

  • Task Name: SystemCheck
    Trigger: Daily: At 12:00 AM every day - After triggered, repeat every 00:01:00 indefinitely.
    Action: %userprofile%\AppData\Roaming\Microsoft\Windows\Helper.exe -SystemCheck

It deletes the following files to remove its traces in the system:

  • %User Temp%\asacpiex.dll -> archive file containing Coinminer.Win64.MOOZ.THCCABO
  • %User Temp%\CR_Debug_Log.txt -> archive file containing Coinminer.Win64.MOOZ.THCCABO
  • %User Temp%\CL_Debug_Log.txt -> 7-zip Archiver
  • %User Temp%\64.exe -> detected as Coinminer.Win64.MOOZ.THCCABO
  • %User Temp%\SystemCheck.xml

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

  SOLUTION

Minimum Scan Engine: 9.850
FIRST VSAPI PATTERN FILE: 15.776.04
FIRST VSAPI PATTERN DATE: 31 Mar 2020
VSAPI OPR PATTERN File: 15.777.00
VSAPI OPR PATTERN Date: 01 Apr 2020

Step 1

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 2

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 3

To delete the added Scheduled Task file:

For Windows 7, Windows Server 2008 (R2), Windows 8, Windows 8.1, Windows 10, and Windows Server 2012 (R2):

  1. Open the Windows Task Scheduler. To do this:
    • On Windows 7, and Windows Server 2008 (R2), click Start, type taskschd.msc in the Search input field, then press Enter.
    • On Windows 8, Windows 8.1, 10 and Windows Server 2012 (R2), right-click on the lower left corner of the screen, click Run, type taskschd.msc, then press Enter.
  2. In the left panel, click Task Scheduler Library.
  3. In the upper-middle panel, select a Task.
  4. Check if the selected task starts the malware automatically. To do this, check the value in the Details column under the Actions tab in the lower-middle panel.
  5. If the malware path and filename are found, press DELETE and click Yes to delete the task.
  6. Repeat the steps above for the remaining tasks.

Step 4

Scan your computer with your Trend Micro product to delete files detected as Trojan.Win32.MOOZ.THCCABO. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check the following Trend Micro Support pages for more information:


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