C++ based bot with DDOS and spying capabilities

May 10, 2013

Dell SonicWALL Threats Research team came across a C++ based bot with DDoS capabilities along with multiple commands to spy on a victim and report its findings back to the Command & Control (C&C) server.

Infection Cycle:

Upon execution the Malware drops the following file on the system:

  • %USERPROFILE%Application Datadropped.exe (Copy of itself)

The Malware adds the following keys to the registry to enable startup after reboot:

  • HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionRunvnet "%USERPROFILE%Application Datadropped.exe"

It makes the following changes to the registry in order to bypass firewalls:

  • HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionInternet SettingsZonemapProxyBypass="1"
  • HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionInternet SettingsZonemapIntranetName="1"
  • HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionInternet SettingsZonemapUNCAsIntranet="1"

It creates the following Mutexes on the system to mark its presence :

  • IESQMMUTEX_0_208
  • VN_MUTEX16

The Malware communicates with the server at www.holoscripter.co-m.mx. One of the parameters used during the communication is 'adduser' followed by information about the victim machine. This appears to be registering the computer on the server as a victim.

The Malware communicates with the C&C server through HTTP where the commands to be executed are present in the response messages. During our analysis we observed the following commands present in the code:

Based on the commands and the following observations we can infer that this is infact VertexNet Bot v1.2:

  • The string 'vertexnet' present in the code

  • The version number present in the code

  • HKNAME in the resource section is vnet

  • One of the Mutexes created is named VN_MUTEX16

The functionalities of VertexNet indicate that this bot has been designed to gather sensitive information about the victim and report it back to the server. Additionally this bot also has DDoS capabilities owing to httpflood command.

Dell SonicWALL Gateway AntiVirus provides protection against this threat via the following signature:

  • GAV: VertexNet.BT (Trojan)