Analysis by: Jeffrey Francis Bonaobra
ALIASES:

Worm:Win32/AutoRun!atmn (MICROSOFT), Win32/Delf.NBX virus (NOD32)

 PLATFORM:

Windows

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

  • Threat Type: Virus

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This Virus 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: 771,584 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 09 Aug 2022

Arrival Details

This Virus 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 Virus adds the following folders:

  • %Application Data%\WinSl
  • %ProgramData%\Synaptics
  • %ProgramData%\Synaptics\WS

(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).. %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit), or C:\Documents and Settings\All Users on Windows Server 2003(32-bit), 2000(32-bit) and XP.)

It drops the following copies of itself into the affected system:

  • %ProgramData%\Synaptics\Synaptics.exe
  • %User Temp%\{random characters}.exe

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit), or C:\Documents and Settings\All Users on Windows Server 2003(32-bit), 2000(32-bit) and XP.. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It drops the following files:

  • %User Temp%\{random characters}.ico
  • %User Temp%\RCX{random characters}.tmp
  • %User Temp%\Tar{random characters}.tmp
  • %User Temp%\Cab{random characters}.tmp

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following processes:

  • "%ProgramData%\Synaptics\Synaptics.exe" InjUpdate

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit), or C:\Documents and Settings\All Users on Windows Server 2003(32-bit), 2000(32-bit) and XP.)

It modifies file attributes to make files hidden.

Autostart Technique

This Virus adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Synaptics Pointing Device Driver = %ProgramData%\Synaptics\Synaptics.exe

Other Details

This Virus connects to the following possibly malicious URL:

  • http://freedns.{BLOCKED}d.org/api/?action=getdyndns&sha={hash value}
  • https://docs.{BLOCKED}e.com
  • http://www.download.{BLOCKED}supdate.com/msdownload/update/v3/static/trustedr/en/authrootstl.cab

  SOLUTION

Minimum Scan Engine: 9.800
FIRST VSAPI PATTERN FILE: 17.198.08
FIRST VSAPI PATTERN DATE: 17 Nov 2021
VSAPI OPR PATTERN File: 17.199.00
VSAPI OPR PATTERN Date: 18 Nov 2021

Step 1

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 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

Delete this registry value

[ 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.

 
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • Synaptics Pointing Device Driver = %ProgramData%\Synaptics\Synaptics.exe

Step 4

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.
  • %ProgramData%\Synaptics\Synaptics.exe
  • %User Temp%\{random characters}.exe
  • %User Temp%\{random characters}.ico
  • %User Temp%\RCX{random characters}.tmp
  • %User Temp%\Tar{random characters}.tmp
  • %User Temp%\Cab{random characters}.tmp

Step 5

Search and delete this folder

[ 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%\WinSl
  • %ProgramData%\Synaptics
  • %ProgramData%\Synaptics\WS

Step 6

Scan your computer with your Trend Micro product to delete files detected as Virus.Win32.NAPWHICH.D.orig. 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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