Trojan.Win32.SMOKELOADER.AI

 Modified by: Emilio Marcel Garcia

 ALIASES:

Trojan:Win32/Gapined.DSK!MTB (MICROSOFT); Trojan.Win32.Bsymem.ntt (KASPERSKY)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware

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.

As of this writing, the said sites are inaccessible.

It terminates itself if it detects it is being run in a virtual environment. It deletes itself after execution.

  TECHNICAL DETAILS

File Size:

194,560 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

06 Feb 2020

Payload:

Downloads files, Connects to URLs/IPs, Drops files, Deletes files, Terminates processes, Steals 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 drops the following copies of itself into the affected system:

  • %Application Data%\{random} -> filename is generated from system information

(Note: %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).)

It drops the following files:

  • %User Temp%\4DD3.tmp -> copy of %System%\ntdll.dll
  • %Application Data%\{random} -> XML file to run the dropped copy of itself; filename is generated from system information
  • %Application Data%\{random} -> downloaded component from C&C server; filename is generated from system information

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %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).)

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

  • {Random hash from system info}
  • opera_shared_counter

It injects codes into the following process(es):

  • explorer.exe

It modifies file attributes to make files hidden.

Other System Modifications

This Trojan deletes the following files:

  • %Application Data%\{dropped copy}:Zone.Identifier

(Note: %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).)

Process Termination

This Trojan terminates the following processes if found running in the affected system's memory:

  • x64dbg.exe
  • x32dbg.exe
  • autoruns.exe
  • idaq64.exe
  • idaq.exe
  • idaw64.exe
  • idaw.exe
  • ollydbg.exe
  • processhacker.exe
  • procexp.exe
  • procmon.exe
  • tcpview.exe
  • wireshark.exe

Download Routine

This Trojan connects to the following URL(s) to download its component file(s):

  • http://{BLOCKED}older131-service.space/

As of this writing, the said sites are inaccessible.

Information Theft

This Trojan gathers the following data:

  • Computer Name
  • User Name
  • System Volume Information
  • Credentials used in the following protocols:
    • ftp
    • smtp
    • pop3
    • imap
  • Data being sent from the following browsers:
    • Firefox
    • Internet Explorer
    • Edge
    • Chrome
    • Opera

Stolen Information

This Trojan sends the gathered information via HTTP POST to the following URL:

  • http://{BLOCKED}older231-service.space/

Other Details

This Trojan terminates itself if it detects it is being run in a virtual environment.

It deletes itself after execution.

It checks if the following virtual machine or sandbox related module(s) is loaded in the affected system:

  • sbiedll

It checks if the following virtual machine- or sandbox-related registry keys are present in the affected system:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControLSet\
Enum\IDE\{*vm string*}
where vm string = qemu; virtio; vmware; vbox; xen

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControLSet\
Enum\SCSI\{*vm string*}
where vm string = qemu; virtio; vmware; vbox; xen

It does not proceed to its malicious routine if it detects that it is being debugged.

It adds the following scheduled tasks:

  • NvNgxUpdateCheckDaily_{%08X-%04X-%04X-%04X-%08X%04X}
  • Task Action: regsvr32 /s /n /u /i:"%Application Data%\{XML file}" scrobj

(Note: %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).)

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

15.670.02

FIRST VSAPI PATTERN DATE:

07 Feb 2020

VSAPI OPR PATTERN File:

15.671.00

VSAPI OPR PATTERN Date:

08 Feb 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.XXPE50FFF033

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

Deleting Scheduled Tasks

The following {Task Name} - {Task to be run} listed should be used in the steps identified below: ul>

  • NvNgxUpdateCheckDaily_{%08X-%04X-%04X-%04X-%08X%04X} - "regsvr32 /s /n /u /i:"%Application Data%\{XML file} scrobj"

  • For Windows 2000, Windows XP, and Windows Server 2003:

    1. Open the Windows Scheduled Tasks. Click Start>Programs>Accessories>
      System Tools>Scheduled Tasks.
    2. Locate each {Task Name} values listed above in the Name column.
    3. Right-click on the said file(s) with the aforementioned value.
    4. Click on Properties. In the Run field, check for the listed {Task to be run}.
    5. If the strings match the list above, delete the task.

    For Windows Vista, Windows 7, Windows Server 2008, Windows 8, Windows 8.1, and Windows Server 2012:

    1. Open the Windows Task Scheduler. To do this:
      • On Windows Vista, Windows 7, and Windows Server 2008, click Start, type taskschd.msc in the Search input field, then press Enter.
      • On Windows 8, Windows 8.1, and Windows Server 2012, 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, locate each {Task Name} values listed above in the Name column.
    4. In the lower-middle panel, click the Actions tab. In the Details column, check for the {Task to be run} string.
    5. If the said string is found, delete the task.

    Step 6

    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.  
    • %User Temp%\4DD3.tmp
    • %Application Data%\{random}
    • %Application Data%\{random}
    • %Application Data%\{random}

    Step 7

    Restart in normal mode and scan your computer with your Trend Micro product for files detected as Trojan.Win32.SMOKELOADER.AI. 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 this Knowledge Base page for more information.


    Did this description help? Tell us how we did.