PUA.Win32.ByteFence.C

June 04, 2020
 PLATFORM:

Windows

 OVERALL RISK RATING:
 REPORTED INFECTION:
 SYSTEM IMPACT RATING:
 INFORMATION EXPOSURE:

  • Threat Type: Potentially Unwanted Application

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This Potentially Unwanted Application 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:

14,972,408 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

04 Jun 2020

Arrival Details

This Potentially Unwanted Application 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 Potentially Unwanted Application adds the following processes:

  • "%User Temp%\InstallTools.exe" "{malware file path and name}" Software\ByteFence INSNDE "{malware file path and name}" /mode=s /url=logs.bytefence.com/event /product=Bytefence
  • taskkill /f /im ByteFence.exe
  • taskkill /f /im ByteFenceService.exe
  • taskkill /f /im ByteFenceScan.exe
  • taskkill /f /im rsEngineHelper.exe
  • taskkill /f /im rsLggr.exe
  • "%System Root%\Program Files\ByteFence\ByteFenceService.exe" -i
  • "%System Root%\Program Files\ByteFence\ByteFenceService.exe"

It creates the following folders:

  • %System Root%\Program Files\ByteFence
  • %System Root%\Program Files\ByteFence\x64
  • %System Root%\Program Files\ByteFence\x86
  • %System Root%\Program Files\ByteFence\amd64

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

Autostart Technique

This Potentially Unwanted Application registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ByteFenceService
ImagePath = "%System Root%\Program Files\ByteFence\ByteFenceService.exe"

Other System Modifications

This Potentially Unwanted Application adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
INSNDE = "{random characters}"

HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
NDLAFLT = ""

HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
NDLCHAN = ""

HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
AFLTCREATED = "1589423755"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
Microsoft\Windows\CurrentVersion\
Uninstall\ByteFence
DisplayName = "ByteFence Anti-Malware"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
Microsoft\Windows\CurrentVersion\
Uninstall\ByteFence
UninstallString = "%System Root%\Program Files\ByteFence\uninstall.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
Microsoft\Windows\CurrentVersion\
Uninstall\ByteFence
Publisher = "Byte Technologies LLC"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
Microsoft\Windows\CurrentVersion\
Uninstall\ByteFence
InstallSource = "%System Root%\Program Files\ByteFence"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
Microsoft\Windows\CurrentVersion\
Uninstall\ByteFence
DisplayVersion = "5.6.2.0"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
Microsoft\Windows\CurrentVersion\
Uninstall\ByteFence
DisplayIcon = "%System Root%\Program Files\ByteFence\Uninstall.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
Microsoft\Windows\CurrentVersion\
Uninstall\ByteFence
URLInfoAbout = "https://www.{BLOCKED}nce.com"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
Microsoft\Windows\CurrentVersion\
Uninstall\ByteFence
NoModify = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
Microsoft\Windows\CurrentVersion\
Uninstall\ByteFence
NoRepair = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
PINSTP = "/LM=3 /INSTEX /cd=12345 /thankyou /IGNORE={malware file path and name}"

HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
INSTUID = "{{GUID}}"

HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
MOLOG = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
ByteFence
PINSTP = "/LM=3 /INSTEX /cd=12345 /thankyou /IGNORE={malware file path and name}"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
ByteFence
INSTUID = "{{GUID}}"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
ByteFence
MOLOG = "0"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\eventlog\Application
AutoBackupLogFiles = "0"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
services\eventlog\Application\
ByteFenceService
EventMessageFile = "%Windows%\Microsoft.NET\Framework64\v2.0.50727\EventLogMessages.dll"

HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
FirstRun = "2/5/2020 12:54:15 PM"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
ByteFence
FirstRun = "2/5/2020 12:54:15 PM"

HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
U = "{GUID}"

HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
UH = "D7EA828DDEFDC9EDB4B37ABDB24BBE8B"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
ByteFence
U = "{GUID}"

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\
ByteFence
UH = "D7EA828DDEFDC9EDB4B37ABDB24BBE8B"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ByteFenceService
DisplayName = "ByteFence Anti-Malware Service"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ByteFenceService
Start = "SERVICE_AUTO_START"

Dropping Routine

This Potentially Unwanted Application drops the following files:

  • %System Root%\Program Files\ByteFence\InstallUtil.InstallLog
  • %System Root%\Program Files\ByteFence\x86\ext_x86.dll
  • %System Root%\Program Files\ByteFence\Uninstall.exe
  • %System Root%\Program Files\ByteFence\amd64\KernelTraceControl.dll
  • %System Root%\Program Files\ByteFence\rsEngineHelper.exe.config
  • %User Temp%\bytefence-installer-5.6.2.0.exe
  • %System Root%\Program Files\ByteFence\ByteFenceService.InstallState
  • %System Root%\Program Files\ByteFence\x86\rsEngineFW_x86.dll
  • %System Root%\Program Files\ByteFence\rsUtils.dll
  • %System Root%\Program Files\ByteFence\ByteFenceService.InstallLog
  • %System Root%\Program Files\ByteFence\EULA.txt
  • %System Root%\Program Files\ByteFence\x64\System.Data.SQLite.dll
  • %System Root%\Program Files\ByteFence\x64\ext_x64.dll
  • %System Root%\Program Files\ByteFence\x64\rsEngineFW_x64.dll
  • %System Root%\Program Files\ByteFence\ByteFenceService.exe
  • %System Root%\Program Files\ByteFence\x86\7z86.dll
  • %System Root%\Program Files\ByteFence\ByteFenceScan.exe
  • %System Root%\Program Files\ByteFence\x86\msdia140.dll
  • %System Root%\Program Files\ByteFence\x86\lz4_x86.dll
  • %System Root%\program files\bytefence\rsEngine.config
  • %System Root%\Program Files\ByteFence\Signatures.dat
  • %System Root%\Program Files\ByteFence\x64\7z64.dll
  • %System Root%\Program Files\ByteFence\protobuf-net.dll
  • %System Root%\Program Files\ByteFence\ByteFence.exe
  • %System Root%\Program Files\ByteFence\Microsoft.Win32.TaskScheduler.dll
  • %System Root%\Program Files\ByteFence\rsEngineHelper.exe
  • %System Root%\Program Files\ByteFence\x64\rsLggrServer_x64.dll
  • %System Root%\Program Files\ByteFence\Microsoft.Diagnostics.Tracing.TraceEvent.dll
  • %User Temp%\InstallTools.exe
  • %System Root%\Program Files\ByteFence\x86\rsEnginePM_x86.dll
  • %System Root%\Program Files\ByteFence\websocket-sharp.dll
  • %System Root%\Program Files\ByteFence\ByteFenceService.exe.config
  • %System Root%\Program Files\ByteFence\ByteFenceGUI.dll
  • %System Root%\Program Files\ByteFence\WhiteList.dat
  • %System Root%\Program Files\ByteFence\amd64\msdia140.dll
  • %System Root%\Program Files\ByteFence\Errors.dat
  • %System Root%\Program Files\ByteFence\x86\KernelTraceControl.dll
  • %System Root%\Program Files\ByteFence\x64\lz4_x64.dll
  • %System Root%\Program Files\ByteFence\x86\System.Data.SQLite.dll
  • %System Root%\Program Files\ByteFence\rsEngine.dll
  • %System Root%\Program Files\ByteFence\x64\rsEnginePM_x64.dll
  • %System Root%\Program Files\ByteFence\ByteFence.exe.config
  • %System Root%\Program Files\ByteFence\rsMessages.dll
  • %System Root%\Program Files\ByteFence\dummy.dat
  • %System Root%\Program Files\ByteFence\x86\rsLggrServer_x86.dll

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

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.850

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

Identify and terminate files detected as PUA.Win32.ByteFence.C

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

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\ByteFence
    • INSNDE = "{random characters}"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
    • NDLAFLT = ""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
    • NDLCHAN = ""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
    • AFLTCREATED = "1589423755"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\ByteFence
    • DisplayName = "ByteFence Anti-Malware"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\ByteFence
    • UninstallString = "%System Root%\Program Files\ByteFence\uninstall.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\ByteFence
    • Publisher = "Byte Technologies LLC"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\ByteFence
    • InstallSource = "%System Root%\Program Files\ByteFence"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\ByteFence
    • DisplayVersion = "5.6.2.0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\ByteFence
    • DisplayIcon = "%System Root%\Program Files\ByteFence\Uninstall.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\ByteFence
    • URLInfoAbout = "https://www.{BLOCKED}nce.com"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\ByteFence
    • NoModify = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\ByteFence
    • NoRepair = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
    • PINSTP = "/LM=3 /INSTEX /cd=12345 /thankyou /IGNORE={malware file path and name}"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
    • INSTUID = "{{GUID}}"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
    • MOLOG = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ByteFence
    • PINSTP = "/LM=3 /INSTEX /cd=12345 /thankyou /IGNORE={malware file path and name}"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ByteFence
    • INSTUID = "{{GUID}}"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ByteFence
    • MOLOG = "0"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\eventlog\Application
    • AutoBackupLogFiles = "0"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\services\eventlog\Application\ByteFenceService
    • EventMessageFile = "%Windows%\Microsoft.NET\Framework64\v2.0.50727\EventLogMessages.dll"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
    • FirstRun = "2/5/2020 12:54:15 PM"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ByteFence
    • FirstRun = "2/5/2020 12:54:15 PM"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
    • U = "{GUID}"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\ByteFence
    • UH = "D7EA828DDEFDC9EDB4B37ABDB24BBE8B"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ByteFence
    • U = "{GUID}"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ByteFence
    • UH = "D7EA828DDEFDC9EDB4B37ABDB24BBE8B"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ByteFenceService
    • DisplayName = "ByteFence Anti-Malware Service"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ByteFenceService
    • Start = "SERVICE_AUTO_START"

Step 4

Search and delete these components

[ Learn More ]
There may be some components 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%\Program Files\ByteFence\InstallUtil.InstallLog
  • %System Root%\Program Files\ByteFence\x86\ext_x86.dll
  • %System Root%\Program Files\ByteFence\Uninstall.exe
  • %System Root%\Program Files\ByteFence\amd64\KernelTraceControl.dll
  • %System Root%\Program Files\ByteFence\rsEngineHelper.exe.config
  • %User Temp%\bytefence-installer-5.6.2.0.exe
  • %System Root%\Program Files\ByteFence\ByteFenceService.InstallState
  • %System Root%\Program Files\ByteFence\x86\rsEngineFW_x86.dll
  • %System Root%\Program Files\ByteFence\rsUtils.dll
  • %System Root%\Program Files\ByteFence\ByteFenceService.InstallLog
  • %System Root%\Program Files\ByteFence\EULA.txt
  • %System Root%\Program Files\ByteFence\x64\System.Data.SQLite.dll
  • %System Root%\Program Files\ByteFence\x64\ext_x64.dll
  • %System Root%\Program Files\ByteFence\x64\rsEngineFW_x64.dll
  • %System Root%\Program Files\ByteFence\ByteFenceService.exe
  • %System Root%\Program Files\ByteFence\x86\7z86.dll
  • %System Root%\Program Files\ByteFence\ByteFenceScan.exe
  • %System Root%\Program Files\ByteFence\x86\msdia140.dll
  • %System Root%\Program Files\ByteFence\x86\lz4_x86.dll
  • %System Root%\program files\bytefence\rsEngine.config
  • %System Root%\Program Files\ByteFence\Signatures.dat
  • %System Root%\Program Files\ByteFence\x64\7z64.dll
  • %System Root%\Program Files\ByteFence\protobuf-net.dll
  • %System Root%\Program Files\ByteFence\ByteFence.exe
  • %System Root%\Program Files\ByteFence\Microsoft.Win32.TaskScheduler.dll
  • %System Root%\Program Files\ByteFence\rsEngineHelper.exe
  • %System Root%\Program Files\ByteFence\x64\rsLggrServer_x64.dll
  • %System Root%\Program Files\ByteFence\Microsoft.Diagnostics.Tracing.TraceEvent.dll
  • %User Temp%\InstallTools.exe
  • %System Root%\Program Files\ByteFence\x86\rsEnginePM_x86.dll
  • %System Root%\Program Files\ByteFence\websocket-sharp.dll
  • %System Root%\Program Files\ByteFence\ByteFenceService.exe.config
  • %System Root%\Program Files\ByteFence\ByteFenceGUI.dll
  • %System Root%\Program Files\ByteFence\WhiteList.dat
  • %System Root%\Program Files\ByteFence\amd64\msdia140.dll
  • %System Root%\Program Files\ByteFence\Errors.dat
  • %System Root%\Program Files\ByteFence\x86\KernelTraceControl.dll
  • %System Root%\Program Files\ByteFence\x64\lz4_x64.dll
  • %System Root%\Program Files\ByteFence\x86\System.Data.SQLite.dll
  • %System Root%\Program Files\ByteFence\rsEngine.dll
  • %System Root%\Program Files\ByteFence\x64\rsEnginePM_x64.dll
  • %System Root%\Program Files\ByteFence\ByteFence.exe.config
  • %System Root%\Program Files\ByteFence\rsMessages.dll
  • %System Root%\Program Files\ByteFence\dummy.dat
  • %System Root%\Program Files\ByteFence\x86\rsLggrServer_x86.dll

Step 5

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.
  • %System Root%\Program Files\ByteFence
  • %System Root%\Program Files\ByteFence\x64
  • %System Root%\Program Files\ByteFence\x86
  • %System Root%\Program Files\ByteFence\amd64

Step 6

Scan your computer with your Trend Micro product to delete files detected as PUA.Win32.ByteFence.C. 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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