BKDR_SIMBOT.SME

This backdoor may be dropped by other malware.

It scans the computer for registry keys related to antivirus and security applications. This action allows the malware to possibly avoid detection in the computer.

It executes commands from a remote malicious user, effectively compromising the affected system. It connects to a website to send and receive information.

Arrival Details

This backdoor may be dropped by the following malware:

• TROJ_ARTIEF.FT

Installation

This backdoor drops the following copies of itself into the affected system:

• %User Profile%\Local Settings\{random}.exe

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random} = "%User Profile%\Local Settings\{random}.exe"

Other System Modifications

This backdoor scans the system for the following registry keys, which are related to antivirus and security applications:

HKEY_LOCAL_MACHINE\SOFTWARE\McAfee

Backdoor Routine

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

• Download and execute files
• Execute a DOS command sent by the remote user
• Send an encrypted copy of the content of a specified file to its C&C server
• Sleeps for a specified amount of time

It connects to the following websites to send and receive information:

• {BLOCKED}.103.58

NOTES:

If the registry, HKEY_LOCAL_MACHINE\SOFTWARE\McAfee is found on the system, it adds the following process:

• services.exe

It then injects itself into the said process as part of its memory residency routine.

If the registry is not found, it adds the following process:

• svchost.exe

It injects itself into that process as part of its memory residency routine.

It communicates with its C&C server by sending the following HTTP request:

• http://{C&C}/{random characters}.php?id={encoded adapter information of the affected machine}

The {random} file name of dropped copy/registry value name above can be any of the inactive services on the system.