BKDR_ANDROM.SMRA

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 may be dropped by other malware.

It deletes registry entries, causing some applications and programs to not function properly.

It does not have any propagation routine.

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.

It may be dropped by the following malware:

• TROJ_ANDROM.SVN

Installation

This Backdoor adds the following processes:

• msiexec.exe

It injects codes into the following process(es):

• created msiexec.exe

Other System Modifications

This Backdoor deletes the following registry entries:

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Image File Execution Options\
taskmgr.exe
Debugger = "taskmgr.exe"

Propagation

This Backdoor does not have any propagation routine.

Backdoor Routine

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

• Start a Process
• Download a file directed by C&C server, save it as %User Temp%\KB{8 random numbers}.exe and execute it
• Copy %System%\cdosys.dll to %User Temp%\cdo{random number}.dll and load it
• Uninstall itself

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

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

• http://{BLOCKED}entia.ru/diff.php
• http://{BLOCKED}trivia.ru/atomic.php

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

Information Theft

This Backdoor gathers the following data:

• Root Volume Serial Number
• Operating System Version
• Local IP Address
• Administrator privileges

Other Details

This Backdoor connects to the following URL(s) to check for an Internet connection:

• update.microsoft.com
• microsoft.com
• google.com
• bing.com
• yahoo.com

It does the following:

• Checks if the following processes related to virtual environment, emulation software, and network monitoring software are running in the affected machine. If so, it will perform infinite sleep.
  • avpui.exe
  • filemon.exe
  • netmon.exe
  • perl.exe
  • prl_cc.exe
  • prl_tools_service.exe
  • prl_tools.exe
  • procmon.exe
  • python.exe
  • regmon.exe
  • sandboxiedcomlaunch.exe
  • sandboxierpcss.exe
  • sharedintapp.exe
  • vboxservice.exe
  • vboxtray.exe
  • vmsrvc.exe
  • vmtoolsd.exe
  • vmusrvc.exe
  • vmwareservice.exe
  • vmwareuser.exe
  • wireshark.exe
• It will not proceed with its routine if the system's language is any of the following:
  • Russian
  • Ukrainian
  • Belarusian
  • Kazakh
• Connects to the following Network Time Protocol (NTP) servers:
  • pool.ntp.org
  • africa.pool.ntp.org
  • oceania.pool.ntp.org
  • asia.pool.ntp.org
  • south-america.pool.ntp.org
  • north-merica.pool.ntp.org
  • europe.pool.ntp.org
• It will not proceed with its routine if the current filename of the malware is any of the following:
  • C:\t.exe
  • C:\myapp.exe
  • C:\self.exe
  • C:\file.exe
  • C:\sample.exe