BKDR_HUPIGON.ZVZ

Upon execution, the main component of this backdoor attempts to load TestDll.dll, which is also detected as BKDR_HUPIGON.ZVZ. This .DLL then creates another .DLL, msnstp.dll and registers it as a service.

It connects to certain servers to wait for commands coming from a remote user.

It then obtains the affected system's IP and MAC address to initiates the connection. If the connection is successful, it waits for certain commands.

This backdoor may be downloaded by other malware/grayware/spyware from remote sites. It may be dropped by other malware. It may be unknowingly downloaded by a user while visiting malicious websites.

Arrival Details

This backdoor may be downloaded by other malware/grayware/spyware from remote sites.

It may be dropped by other malware.

It may be unknowingly downloaded by a user while visiting malicious websites.

Installation

This backdoor drops and executes the following files:

• %System%\msnstp.dll - also detected as BKDR_HUPIGON.ZVZ

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

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

• afsdioufaiowehnjkrhfsdjkf

Autostart Technique

This backdoor 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\Irmon
ImagePath = "%System%\svchost.exe -k netsvcs"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Irmon
Type = "20"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Irmon
Start = "2"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Irmon
ErrorControl = "1"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Irmon
ObjectName = "LocalSystem"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Irmon\Parameters HKEY_LOCAL_MACHINE\
SYSTEM\CurrentControlSet\Services\
Irmon\Parameters
ServiceDll = "%System%\msnstp.dll"

NOTES:

Upon execution, its main component attempts to load TestDll.dll, which is also detected as BKDR_HUPIGON.ZVZ. This .DLL then creates another .DLL, msnstp.dll and registers it as a service.

Backdoor Routine

It connects to the following servers to wait for commands coming from a remote user:

• {BLOCKED}2009.{BLOCKED}fw.us
• {BLOCKED}2009.{BLOCKED}ogle.com

It then obtains the affected system's IP and MAC address to initiates the connection. If the connection is successful, it waits for commands such as the following:

• cmdview+
• delete++
• downfold
• download
• downstop
• execute+
• getdrive
• process+
• uninstal
• update++

The server's reply should start with "#@$"

It may perform the following depending on the received command:

• Delete files
• Download / upload files
• Download folder
• Execute commands using cmd.exe
• Execute files
• Get drives
• List / kill processes
• Stop download
• Uninstall backdoor
• Update itself