Backdoor.Win32.COTX.YPAL-A

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.

It executes commands from a remote malicious user, effectively compromising the affected system. However, as of this writing, the said sites are inaccessible.

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 drops the following copies of itself into the affected system:

• %Program Files%\Intel\Intel(R) Processor Graphics\RasTls.dll

(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000(32-bit), Server 2003(32-bit), XP, Vista(64-bit), 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit) , or C:\Program Files (x86) in Windows XP(64-bit), Vista(64-bit), 7(64-bit), 8(64-bit), 8.1(64-bit), 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It drops the following files:

• %User Temp%\UnI{4 Hex Characters}.bat -> Bat file to delete {AcroRd32.exe or IntelGraphicsController.exe}
• %User Temp%\UnI{4 Hex Characters}.bat -> Bat file to delete RasTls.dll (Original Self)
• %Program Files%\Intel\Intel(R) Processor Graphics\IntelGraphicsController.exe

(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).. %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000(32-bit), Server 2003(32-bit), XP, Vista(64-bit), 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit) , or C:\Program Files (x86) in Windows XP(64-bit), Vista(64-bit), 7(64-bit), 8(64-bit), 8.1(64-bit), 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following processes:

• %System%\cmd.exe /c icacls %Program Files%\Intel\Intel(R) Processor Graphics\IntelGraphicsController.exe /grant administrators:F
• %System%\cmd.exe /c icacls %Program Files%\Intel\Intel(R) Processor Graphics\RasTls.dll /grant administrators:F
• %System%\cmd.exe /c icacls %Program Files%\Intel\Intel(R) Processor Graphics\IntelGraphicsController.exe /grant users:F
• %System%\cmd.exe /c icacls %Program Files%\Intel\Intel(R) Processor Graphics\RasTls.dll /grant users:F
• %System%\dllhost.exe /Processid:{Generated GUID}
• %System%\cmd.exe /c "rd /s /q %ProgramData%\Windows\Intel\Up\*

(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000(32-bit), Server 2003(32-bit), XP, Vista(64-bit), 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit) , or C:\Program Files (x86) in Windows XP(64-bit), Vista(64-bit), 7(64-bit), 8(64-bit), 8.1(64-bit), 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 creates the following folders:

• %Program Files%\Intel\
• %Program Files%\Intel\Intel(R) Processor Graphics\
• %ProgramData%\Windows\Intel
• %ProgramData%\Windows\Intel\Up\

(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000(32-bit), Server 2003(32-bit), XP, Vista(64-bit), 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit) , or C:\Program Files (x86) in Windows XP(64-bit), Vista(64-bit), 7(64-bit), 8(64-bit), 8.1(64-bit), 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 adds the following mutexes to ensure that only one of its copies runs at any one time:

• 11223344556677889900

It injects codes into the following process(es):

• %System%\dllhost.exe /Processid:{Generated GUID}

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

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
IntelGraphicsController = %Program Files%\Intel\Intel(R) Processor Graphics\IntelGraphicsController.exe /Processid:{Generated GUID}

Backdoor Routine

This Backdoor executes the following commands from a remote malicious user:

• Manage Files (Copy,Read,Delete,Write)
• Manage Processes (List Running, Kill)
• Manage Command Shell (Open, Open as User, Kill, Send Commands to Execute)
• Get Drive Info (Drive Type, Disk Space)
• Get Directory Info
• Get List of Installed Software
• Run Executable Files
• Take Screenshot
• Uninstall and Remove Self
• Exit Self
• Update Configuration
• Send Configuration

It connects to the following URL(s) to send and receive commands from a remote malicious user:

• {BLOCKED}213213:443
• {BLOCKED}3213:443

However, as of this writing, the said sites are inaccessible.

Information Theft

This Backdoor gathers the following data:

• Computer Name
• User Name
• OS Version
• OS Architecture
• Local IP Address
• MAC Address

Other Details

This Backdoor adds the following registry keys:

HKEY_LOCAl_MACHINE\SOFTWARE\Intel\
Java
user = {Encrypted String in Base64}

It does the following:

• It compares the process name it is running under and exits if not equal to any of the following:
  • winword.exe
  • excel.exe
  • powerpnt.exe
  • eqnedt32.exe
  • acrord32.exe