Analysis by: Karen Ivy Titiwa
ALIASES:

Trojan:Win32/CoinMiner.BW!bit (MICROSOFT); Trojan.Win32.BitCoinMiner.etj(KASPERSKY)

 PLATFORM:

Windows

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

  • Threat Type: Coinminer

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet

This Coinminer 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: 1,901,568 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 14 Aug 2020
Payload: Connects to URLs/IPs

Arrival Details

This Coinminer 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 Coinminer drops the following files:

  • %ProgramData%\zCKIkINbzT\083626eddd_3.1.0
  • %ProgramData%\zCKIkINbzT\cfgi
  • %ProgramData%\zCKIkINbzT\cfg
  • %ProgramData%\zCKIkINbzT\dll
  • %ProgramData%\zCKIkINbzT\dll.exe
  • %ProgramData%\zCKIkINbzT\r.vbs
  • %User Startup%\ikGYLrmVMj.url

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit), or C:\Documents and Settings\All Users on Windows Server 2003(32-bit), 2000(32-bit) and XP.. %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, C:\Documents and Settings\{User name}\Start Menu\Programs\Startup on Windows 2003(32-bit), XP and 2000(32-bit), or C:\Users\{user name}\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit), 10(64-bit).)

It adds the following processes:

  • cmd.exe /C WScript "%ProgramData%\zCKIkINbzT\r.vbs"
  • "%System%\wuapp.exe" -c "%ProgramData%\zCKIkINbzT\cfg"

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit), or C:\Documents and Settings\All Users on Windows Server 2003(32-bit), 2000(32-bit) and XP.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

  • 083626eddd15ac3f8a72

Other System Modifications

This Coinminer deletes the following files:

  • %ProgramData%\zCKIkINbzT\r.vbs

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit), or C:\Documents and Settings\All Users on Windows Server 2003(32-bit), 2000(32-bit) and XP.)

Download Routine

This Coinminer accesses the following websites to download files:

  • {BLOCKED}bin.com:443

  SOLUTION

Minimum Scan Engine: 9.850
FIRST VSAPI PATTERN FILE: 16.164.05
FIRST VSAPI PATTERN DATE: 14 Aug 2020
VSAPI OPR PATTERN File: 16.165.00
VSAPI OPR PATTERN Date: 14 Aug 2020

Step 1

Trend Micro Predictive Machine Learning detects and blocks malware at the first sign of its existence, before it executes on your system. When enabled, your Trend Micro product detects this malware under the following machine learning name:

     
    • Troj.Win32.TRX.XXPE50FFF036

Step 2

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 3

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 4

Restart in Safe Mode

[ Learn More ]

Step 5

Identify and terminate files detected as Coinminer.Win32.MALXMR.THHADBO

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 6

Search and delete this file

[ Learn More ]
There may be some files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.  
  • %ProgramData%\zCKIkINbzT\083626eddd_3.1.0
  • %ProgramData%\zCKIkINbzT\cfgi
  • %ProgramData%\zCKIkINbzT\cfg
  • %ProgramData%\zCKIkINbzT\dll
  • %ProgramData%\zCKIkINbzT\dll.exe 
  • %ProgramData%\zCKIkINbzT\r.vbs
  • %User Startup%\ikGYLrmVMj.url

Step 7

Scan your computer with your Trend Micro product to delete files detected as Coinminer.Win32.MALXMR.THHADBO. 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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