Analysis by: Rheniel Rhay Ramos
ALIASES:

BDS/ShellCodeF.641 (Avira); Backdoor.Shell.AH (Bitdefender);

 PLATFORM:

Windows

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

  • Threat Type: Coinminer

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel: Dropped by other malware

This Coinminer arrives as a component bundled with malware/grayware packages.

It downloads a file from a certain URL then renames it before storing it in the affected system. It executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system. As of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size: 2,120 bytes
File Type: COM
Memory Resident: No
Initial Samples Received Date: 07 Mar 2018
Payload: Connects to URLs/IPs, Downloads files

Arrival Details

This Coinminer arrives as a component bundled with malware/grayware packages.

Installation

This Coinminer drops and executes the following files:

  • %System Root%\poc.vbs -> used for download routine

(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.)

Download Routine

This Coinminer downloads files from the following URLs then renames them before storage in the affected system:

  • http://{BLOCKED}s.io/ipns/QmahDsXu3KGxzkEoKDe7wqLCgvvo6ADBw6wXUXur5pksM6/tools/xmr-64.exe

It saves the files it downloads using the following names:

  • %System Root%\ime\admissioninit.exe

(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.)

It then executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

As of this writing, the said sites are inaccessible.

Other Details

This Coinminer does the following:

  SOLUTION

Minimum Scan Engine: 9.850
FIRST VSAPI PATTERN FILE: 14.138.04
FIRST VSAPI PATTERN DATE: 19 Mar 2018
VSAPI OPR PATTERN File: 14.139.00
VSAPI OPR PATTERN Date: 20 Mar 2018

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 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

Search and delete these files

[ 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.  
  • %System Root%\poc.vbs
  • %System Root%\ime\admissioninit.exe

Step 4

Scan your computer with your Trend Micro product to delete files detected as COINMINER_MALXMR.A-CMD. 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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