TROJ_MDROPPER.G


 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

  TECHNICAL DETAILS

File Size:

1,070,080 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

05 Sep 2014

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan creates the following folders:

  • %System%\scan
  • download
  • logs
  • sounds

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)

Other System Modifications

This Trojan deletes the following files:

  • %System%\scan\hook.bat
  • %System%\scan\TMP2.$$$

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)

It adds the following registry keys:

HKEY_CURRENT_USER\Software\WinRAR SFX

HKEY_LOCAL_MACHINE\Software\The Silicon Realms Toolworks\
Armadillo

HKEY_CURRENT_USER\Software\mIRC

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Uninstall\
mIRC

HKEY_CLASSES_ROOT\.cha

HKEY_CLASSES_ROOT\.chat

HKEY_CLASSES_ROOT\ChatFile

HKEY_CLASSES_ROOT\ChatFile\DefaultIcon

HKEY_CLASSES_ROOT\ChatFile\Shell\
open\command

HKEY_CLASSES_ROOT\ChatFile\Shell\
open\ddeexec

HKEY_CLASSES_ROOT\ChatFile\Shell\
open\ddeexec\Application

HKEY_CLASSES_ROOT\ChatFile\Shell\
open\ddeexec\ifexec

HKEY_CLASSES_ROOT\ChatFile\Shell\
open\ddeexec\Topic

HKEY_LOCAL_MACHINE\Software\Classes\
irc

HKEY_LOCAL_MACHINE\Software\Classes\
irc\DefaultIcon

HKEY_LOCAL_MACHINE\Software\Classes\
irc\Shell\open\
command

HKEY_LOCAL_MACHINE\Software\Classes\
irc\Shell\open\
ddeexec

HKEY_LOCAL_MACHINE\Software\Classes\
irc\Shell\open\
ddeexec\Application

HKEY_LOCAL_MACHINE\Software\Classes\
irc\Shell\open\
ddeexec\ifexec

HKEY_LOCAL_MACHINE\Software\Classes\
irc\Shell\open\
ddeexec\Topic

It adds the following registry entries:

HKEY_CURRENT_USER\Software\WinRAR SFX
C%%WINDOWS%system32%scan = "%System%\scan"

HKEY_LOCAL_MACHINE\SOFTWARE\The Silicon Realms Toolworks\
Armadillo
{06DDC3B8D534FB67A} = "{random values}"

HKEY_CURRENT_USER\Software\mIRC
DateUsed = "1409721942"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
mIRC
DisplayName = "mIRC"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
mIRC
UninstallString = "%System%\scan\svchost.exe -uninstall"

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
irc
EditFlags = "{random values}"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
VoiceEnabled = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
UseVoiceTips = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
KeyHoldHotKey = "91"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
UseBeepSRPrompt = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
SRTimerDelay = "7d"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
SRModeID = "{random values}"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
EnableSpeaking = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
UseBalloon = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
UseCharacterFont = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
UseSoundEffects = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
SpeakingSpeed = "5"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
PropertySheetX = "f423f"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
PropertySheetY = "f423f"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
PropertySheetWidth = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
PropertySheetHeight = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
PropertySheetPage = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
CommandsWindowLeft = "ffffffff"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
CommandsWindowTop = "ffffffff"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
CommandsWindowWidth = "c8"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
CommandsWindowHeight = "c8"

HKEY_CURRENT_USER\Software\Microsoft\
Microsoft Agent
CommandsWindowLocationSet = "0"

Dropping Routine

This Trojan drops the following files:

  • remote.ini
  • hook.bat
  • services.exe
  • aliases.ini
  • hex.exe
  • mirc.ini
  • nt.dll
  • moo.dll
  • moodll.mrc
  • svchost.exe
  • x.mrc
  • %System%\scan\TMP1.$$$

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.700

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Delete this registry key

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software
    • WinRAR SFX
  • In HKEY_LOCAL_MACHINE\Software\The Silicon Realms Toolworks
    • Armadillo
  • In HKEY_CURRENT_USER\Software
    • mIRC
  • In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Uninstall
    • mIRC
  • In HKEY_CLASSES_ROOT
    • .cha
  • In HKEY_CLASSES_ROOT
    • .chat
  • In HKEY_CLASSES_ROOT
    • ChatFile
  • In HKEY_CLASSES_ROOT\ChatFile
    • DefaultIcon
  • In HKEY_CLASSES_ROOT\ChatFile\Shell\open
    • command
  • In HKEY_CLASSES_ROOT\ChatFile\Shell\open
    • ddeexec
  • In HKEY_CLASSES_ROOT\ChatFile\Shell\open\ddeexec
    • Application
  • In HKEY_CLASSES_ROOT\ChatFile\Shell\open\ddeexec
    • ifexec
  • In HKEY_CLASSES_ROOT\ChatFile\Shell\open\ddeexec
    • Topic
  • In HKEY_LOCAL_MACHINE\Software\Classes
    • irc
  • In HKEY_LOCAL_MACHINE\Software\Classes\irc
    • DefaultIcon
  • In HKEY_LOCAL_MACHINE\Software\Classes\irc\Shell\open
    • command
  • In HKEY_LOCAL_MACHINE\Software\Classes\irc\Shell\open
    • ddeexec
  • In HKEY_LOCAL_MACHINE\Software\Classes\irc\Shell\open\ddeexec
    • Application
  • In HKEY_LOCAL_MACHINE\Software\Classes\irc\Shell\open\ddeexec
    • ifexec
  • In HKEY_LOCAL_MACHINE\Software\Classes\irc\Shell\open\ddeexec
    • Topic

Step 3

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software\WinRAR SFX
    • C%%WINDOWS%system32%scan = "%System%\scan"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\The Silicon Realms Toolworks\Armadillo
    • {06DDC3B8D534FB67A} = "{random values}"
  • In HKEY_CURRENT_USER\Software\mIRC
    • DateUsed = "1409721942"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\mIRC
    • DisplayName = "mIRC"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\mIRC
    • UninstallString = "%System%\scan\svchost.exe -uninstall"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\irc
    • EditFlags = "{random values}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • VoiceEnabled = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • UseVoiceTips = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • KeyHoldHotKey = "91"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • UseBeepSRPrompt = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • SRTimerDelay = "7d"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • SRModeID = "{random values}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • EnableSpeaking = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • UseBalloon = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • UseCharacterFont = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • UseSoundEffects = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • SpeakingSpeed = "5"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • PropertySheetX = "f423f"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • PropertySheetY = "f423f"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • PropertySheetWidth = "0"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • PropertySheetHeight = "0"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • PropertySheetPage = "0"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • CommandsWindowLeft = "ffffffff"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • CommandsWindowTop = "ffffffff"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • CommandsWindowWidth = "c8"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • CommandsWindowHeight = "c8"
  • In HKEY_CURRENT_USER\Software\Microsoft\Microsoft Agent
    • CommandsWindowLocationSet = "0"

Step 4

Search and delete these components

[ Learn More ]
There may be some components that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • remote.ini
  • hook.bat
  • services.exe
  • aliases.ini
  • hex.exe
  • mirc.ini
  • nt.dll
  • moo.dll
  • moodll.mrc
  • svchost.exe
  • x.mrc
  • %System%\scan\TMP1.$
$
  • In the Look In drop-down list, select My Computer then press Enter.
  • Once located, select the file then press SHIFT+DELETE to delete it.
    *Note: The file name input box title varies depending on the Windows version (e.g. Search for files or folders named or All or part of the file name.).
  • • For Windows Vista, Windows 7, Windows Server 2003 (R2), Windows 8, Windows 8.1, and Windows Server 2012 (R2):

    1. Open a Windows Explorer window.
      • For Windows Vista, 7, and Server 2008 (R2) users, click Start>Computer.
      • For Windows 8, 8.1, and Server 2012 (R2) users, right-click on the lower left corner of the screen,then click File Explorer.
    2. In the Search Computer/This PC input box, type:
      • remote.ini
      • hook.bat
      • services.exe
      • aliases.ini
      • hex.exe
      • mirc.ini
      • nt.dll
      • moo.dll
      • moodll.mrc
      • svchost.exe
      • x.mrc
      • %System%\scan\TMP1.$
    3. Once located, select the file then press SHIFT+DELETE to delete it.
      *Note: Read the following Microsoft page if these steps do not work on Windows 7.

    Step 5

    Search and delete these folders

    [ Learn More ]
    Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
    • %System%\scan
    • download
    • logs
    • sounds

    Step 6

    Scan your computer with your Trend Micro product to delete files detected as TROJ_MDROPPER.G. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.

    Step 7

    Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

    • %System%\scan\hook.bat
    • %System%\scan\TMP2.$


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