BKDR_MIDHOS.DMS

This backdoor may be dropped by other malware.

It runs certain commands that it receives remotely from a malicious user. Doing this puts the affected computer and information found on the computer at greater risk.

It deletes the initially executed copy of itself.

Arrival Details

This backdoor may be dropped by the following malware:

• TROJ_ARTIEF.ADQ
• TROJ_ARTIEF.DMX

Installation

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

• %User Temp%\conime.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, XP, and Server 2003.)

It drops the following files:

• %User Temp%\conime.dll - also detected by Trend Micro as BKDR_MIDHOS.DMS
• %User Temp%\conime.inf

(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, XP, and Server 2003.)

It terminates the execution of the copy it initially executed and executes the copy it drops instead.

Autostart Technique

This backdoor drops the following file(s) in the Windows User Startup folder to enable its automatic execution at every system startup:

• %User Startup%\Updata.lnk

(Note: %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup.)

Backdoor Routine

This backdoor executes the following command(s) from a remote malicious user:

• Get drive space information
• List the contents of a directory
• Delete a file
• Download a file from the C&C server
• Upload a file to the C&C server
• Create a process
• Enumerate processes
• Terminate a process
• Start a remote command prompt
• Run a command and send the results
• Take a screenshot
• Update configuration file
• Uninstall itself
• Set current directory

Other Details

This backdoor deletes the initially executed copy of itself

NOTES:

This backdoor sets the attributes of the following folder to Hidden:

• %User Startup%

It checks if the following registry entry is present on the affected system:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run 360Safetray

If it does not exist, it starts a hidden instance of Internet Explorer which loads the component CONIME.DLL automatically. If it exists, it calls the component CONIME.DLL directly.

The said DLL component contains the backdoor routines of this malware. The configuration file CONIME.INF contains the address of the C&C server and the port it uses to connect. The default contents of the configuration file points to the C&C server {BLOCKED}.{BLOCKED}.77.98:1080.