Analysis by: Jay Garcia
ALIASES:

Trj/TrickBot.A (Panda); Trojan:Win32/Trickbot.BS!MTB (Microsoft)

 PLATFORM:

Windows

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

  • Threat Type: Trojan Spy

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This Trojan Spy 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: 397,312 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 16 Mar 2020

Arrival Details

This Trojan Spy 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 Spy drops the following copies of itself into the affected system:

  • %Application Data%\NetCoreLibrary\{Malware name}.exe

(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:

  • %Application Data%\NetCoreLibrary\settings.ini
  • %Application Data%\NetCoreLibrary\data\networkDll32
  • %Application Data%\NetCoreLibrary\data\pwgrab32
  • %Application Data%\NetCoreLibrary\data\tabDll32
  • %Application Data%\NetCoreLibrary\data\networkDll32_configs\dpost
  • %Application Data%\NetCoreLibrary\data\pwgrab32_configs\dpost

(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 creates the following folders:

  • %Application Data%\NetCoreLibrary\Data
  • %Application Data%\NetCoreLibrary
  • %Application Data%\NetCoreLibrary\data\pwgrab32_configs
  • %Application Data%\NetCoreLibrary\data\networkDll32_configs

(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).)

Other Details

This Trojan Spy connects to the following possibly malicious URL:

  • http://{BLOCKED}.{BLOCKED}.135.102:8082

It adds the following scheduled tasks:

  • Task Name: Windows .Net core library
    Trigger: At Startup
    At {Time Executed} on {Date Executed} - After triggered, repeat every 15 minutes for a duration of 408.10:30:00.
    Action: %Application Data%\NetCoreLibrary\{Malware name}.exe

(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: 15.750.03
FIRST VSAPI PATTERN DATE: 18 Mar 2020
VSAPI OPR PATTERN File: 15.751.00
VSAPI OPR PATTERN Date: 19 Mar 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.XXPE50FFF034

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

For Windows Vista, 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, Windows 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, locate each task that has the value in the Triggers column:
    • Task Name: Windows .Net core library
    • Trigger: At Startup
    • Trigger: At {Time Executed} on {Date Executed} - After triggered, repeat every 15 minutes for a duration of 408.10:30:00.
    • Action: %Application Data%\NetCoreLibrary\{Malware name}.exe
  4. In the lower-middle panel, click the Actions tab. In the Details column, check for the following string:
    Cmd /c /rd /s /q C:
  5. If the said string is found, delete the task..

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.
  • %Application Data%\NetCoreLibrary\settings.ini
  • %Application Data%\NetCoreLibrary\data\networkDll32
  • %Application Data%\NetCoreLibrary\data\pwgrab32
  • %Application Data%\NetCoreLibrary\data\tabDll32
  • %Application Data%\NetCoreLibrary\data\networkDll32_configs\dpost
  • %Application Data%\NetCoreLibrary\data\pwgrab32_configs\dpost

Step 7

Search and delete these folders

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %Application Data%\NetCoreLibrary\Data
  • %Application Data%\NetCoreLibrary
  • %Application Data%\NetCoreLibrary\data\pwgrab32_configs
  • %Application Data%\NetCoreLibrary\data\networkDll32_configs

Step 8

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TrojanSpy.Win32.TRICKBOT.TIGOCGV. 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.


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