Trojan.Win32.COPPERPHISH.FV

April 08, 2024
 Analysis by: Francesca Villasanta
 ALIASES:

HEUR:Trojan.Win32.Invader (KASPERSKY)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • 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.

It executes then deletes itself afterward.

  TECHNICAL DETAILS

File Size:

237,568 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

18 Mar 2024

Payload:

Connects to URLs/IPs, Drops files, Modifies system registry

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 files:

  • %Application Data%\Microsoft\index.html → deleted afterwards
  • %Application Data%\Microsoft\logo.png → deleted afterwards
  • %Application Data%\Microsoft\qrcode.png → deleted afterwards
  • %Windows%\Tasks\{16 Characters Generated}.job → deleted afterwards

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

It adds the following processes:

  • %System%\rundll32.exe
  • cmd /c ping 127.0.0.1 -n 3 & del "{Malware Path}\{Malware Filename}.exe"

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

It executes then deletes itself afterward.

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

  • Global\signature_netcheck

Other System Modifications

This Trojan adds the following registry keys as part of its installation routine:

HKEY_CURRENT_USER\Software\{16 Characters Generated}

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\{16 Characters Generated}
0 = {Hex Values}

Other Details

This Trojan does the following:

  • It deletes the default route from the IP routing table, disabling the communication to the Internet.
  • It starts the RpcSs Service (Remote Procedure Call Service) if not running.
  • It starts the Task Scheduler Service if not running.
  • It checks for the existence of the following window:
    • Window class: ThunderRT6FormDC
      Window Name: Operators Network Error Check
    • If not found, it creates the following process in SUSPENDED state and injects code to it: %System%\rundll32.exe
  • It shows the following "Operators Network Error Check" window, luring the user to scan the QR:
    {copperphish.png}
  • The QR code directs to the following phishing website:
  • It creates a named pipe and connects to it.
    • \.\pipe\microsoft_shutdown_network
  • It reads data from the created pipe and waits for the message signalling that a correct confirmation code is entered.
  • Once a correct confirmation code is supplied
    • Disconnects from the named pipe.
    • Restores the default route of the IP routing table.
    • Deletes the created scheduled task.
    • Closes the "Operators Network Error Check" window.
    • Deletes the following files:
      • %Application Data%\Microsoft\index.html
      • %Application Data%\Microsoft\logo.png
      • %Application Data%\Microsoft\qrcode.png
    • Sends a ping to {BLOCKED}.{BLOCKED}.{BLOCKED}.1
    • Deletes itself.

It adds the following scheduled tasks:

  • Task Name: {16 Characters Generated}
    Trigger: At logon
    Action: Start a program - {Malware Path}\{Malware Filename}

  SOLUTION

Minimum Scan Engine:

9.800

FIRST VSAPI PATTERN FILE:

19.254.03

FIRST VSAPI PATTERN DATE:

02 Apr 2024

VSAPI OPR PATTERN File:

19.255.00

VSAPI OPR PATTERN Date:

03 Apr 2024

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.XXPE50FFF079

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 while in Safe Mode

  1. Still in safe mode, the following {Task Name}-{Task to be run} listed should be used in the steps identified below:
    • Task Name: {16 Characters Generated}
    • Task to be run: Start a program - {Malware Path}\{Malware Filename}
  2. For Windows 7 and Server 2008 (R2) users, click Start>Computer.
    • For Windows 8, 8.1, 10, and Server 2012 users, right-click on the lower left corner of the screen, then click File Explorer.
  3. In the Search Computer/This PC input box, type:
    • %System%\Tasks\{Task Name}
  4. Once located, select the file then press SHIFT+DELETE to delete it.
  5. Open Registry Editor. To do this:
    • For Windows 7 and Server 2008 (R2) users, click the Start button, type regedit in the Search input field, and press Enter.
    • For Windows 8, 8.1, 10, and Server 2012 (R2) users, right-click on the lower left corner of the screen, click Run, type regedit in the text box
  6. In the left panel of the Registry Editor window, double-click the following:
    • HKEY_LOCAL_MACHINE>SOFTWARE>Microsoft>Windows NT>CurrentVersion>Schedule>TaskCache>Tree>{Task Name}
  7. Locate the created entry and take note of the registry value's data:
    • ID={Task Data}
  8. After taking note of the data, delete the registry key:
    • HKEY_LOCAL_MACHINE>SOFTWARE>Microsoft>Windows NT>CurrentVersion>Schedule>TaskCache>Tree>{Task Name}
  9. In the left panel of the Registry Editor window, double-click the following:
    • HKEY_LOCAL_MACHINE>SOFTWARE>Microsoft>Windows NT>CurrentVersion>Schedule>TaskCache>Tasks
  10. Still in the left panel, locate and delete the registry key with the same name as the located Task Data in step #6:
    • ={Task Data}
  11. Close Registry Editor.

Step 6

Delete this registry key

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.

  • In HKEY_CURRENT_USER\Software\{16 Characters Generated}
 RESTORE
  • Close Registry Editor.

    • Step 7

    Search and delete these files

    [ Learn More ]
    There may be some component 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%\Microsoft\index.html
    • %Application Data%\Microsoft\logo.png
    • %Application Data%\Microsoft\qrcode.png
    • %Windows%\Tasks\{16 Characters Generated}.job

    Step 8

    Restart in normal mode and scan your computer with your Trend Micro product for files detected as Trojan.Win32.COPPERPHISH.FV. 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.