Backdoor.Win32.DARKKOMET.AW

This Backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Arrival Details

This Backdoor 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 Backdoor adds the following processes:

• %All Users Profile%\UBlockPlugin\plugin.exe "{malware file path and name}" ensgJJ
• %System%\secinit.exe %All Users Profile%\UBlockPlugin\plugin.exe
• %All Users Profile%\UBlockPlugin\ohuqotygkoru.exe
• %Windows%\SysWOW64\WerFault.exe -u -p 1720 -s 632
• "%System%\cmd.exe" /c timeout -n 7&del $EXEPATH /f
• "%System%\cmd.exe" /c timeout -t 15& powershell -ep bypass -f %User Temp%\evil.ps1
• timeout -n 7
• timeout -t 15
• powershell -ep bypass -f %User Temp%\evil.ps1
• "%System%\cmd.exe" /c del %temp%\*.ps1 /f
• "%System%\cmd.exe" /c del %temp%\*.txt /f
• %System%\svchost.exe -k netsvcs

(Note: %All Users Profile% is the common user's profile folder, which is usually C:\Documents and Settings\All Users on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit). . %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %Windows% is the Windows folder, where it usually is C:\Windows 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).)

It creates the following folders:

• %System Root%\Users
• %User Profile%\AppData
• %All Users Profile%\UBlockPlugin

(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name} on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %All Users Profile% is the common user's profile folder, which is usually C:\Documents and Settings\All Users on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit). )

Other System Modifications

This Backdoor deletes the following files:

• %User Temp%\dd_SetupUtility.txt
• %User Temp%\dd_vcredistMSI0FC1.txt
• %User Temp%\Microsoft .NET Framework 4.5.2 Setup_20161212_135033207-MSI_netfx_Full_GDR_x64.msi.txt
• %User Temp%\dd_vcredistUI0FC1.txt
• %User Temp%\dd_vcredistUI0FD5.txt
• %User Temp%\dd_wcf_CA_smci_20161212_135110_351.txt
• %User Temp%\dd_vcredistMSI0FD5.txt
• %User Temp%\dd_NDP452-KB2901907-x86-x64-AllOS-ENU_decompression_log.txt
• %User Temp%\FXSAPIDebugLogFile.txt
• {malware file path and name}
• %User Temp%\dd_wcf_CA_smci_20161212_135109_353.txt

(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 deletes the following folders:

• %User Temp%\nsuB625.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 registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\Winlogon
Shell = "explorer.exe, %All Users Profile%\UBlockPlugin\plugin.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\Winlogon
qevoygutbyebnyh = "explorer.exe, %All Users Profile%\UBlockPlugin\ohuqotygkoru.exe "

Dropping Routine

This Backdoor drops the following files:

• %All Users Profile%\UBlockPlugin\ohuqotygkoru.exe
• %User Temp%\installscript.txt
• %User Temp%\evil.ps1
• %All Users Profile%\UBlockPlugin\plugin.exe

(Note: %All Users Profile% is the common user's profile folder, which is usually C:\Documents and Settings\All Users on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit). . %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).)

Other Details

This Backdoor connects to the following possibly malicious URL:

• http://{BLOCKED}01.info/{random path}
• http://{BLOCKED}5.17.150/imyafaila.exe

This report is generated via an automated analysis system.