Analysis by: John Rey Canon
ALIASES:

Trojan.VBS.Agent.aal (Kaspersky); VBS.BtcMine.12 (DrWeb); VBS:AgentMiner-A [Trj] (Avast)

 PLATFORM:

Windows

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

  • Threat Type: Coinminer

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

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.

It uses the system's central processing unit (CPU) and/or graphical processing unit (GPU) resources to mine cryptocurrency.

  TECHNICAL DETAILS

File Size: 352,256 bytes
File Type: VBS
Memory Resident: Yes
Initial Samples Received Date: 30 May 2018

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.

Autostart Technique

This Coinminer drops the following file(s) in the Windows User Startup folder to enable its automatic execution at every system startup:

  • %User Startup%\helper.lnk

(Note: %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).)

Other Details

This Coinminer does the following:

  • It uses the following details for its mining capabilities:
    • url: xmr.cryp{BLOCKED}ol.fr:3333
    • user: {BLOCKED}zG5JteZ3wxZNkuKj6onDw9T27QoPxeBpv8ira5s7cZLS2Yz7KqwRD6ok4bjYp6PWkAiJMKjuQXo3wUh8PJ8JFwE
    • password: x

It uses the system's central processing unit (CPU) and/or graphical processing unit (GPU) resources to mine cryptocurrency. This behavior makes the system run abnormally slow.

  SOLUTION

Minimum Scan Engine: 9.850
FIRST VSAPI PATTERN FILE: 15.334.08
FIRST VSAPI PATTERN DATE: 30 Aug 2019
VSAPI OPR PATTERN File: 15.335.00
VSAPI OPR PATTERN Date: 31 Aug 2019

Step 1

Trend Micro products with the XGen technology detect this malware as

[ Learn More ]

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

Identify and terminate files detected as Coinminer.VBS.MALXMR.TIAR

[ 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 5

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.
  • %User Startup%\helper.lnk

Step 6

Scan your computer with your Trend Micro product to delete files detected as Coinminer.VBS.MALXMR.TIAR. 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:


Did this description help? Tell us how we did.