TROJ_DROPR.LFA

 Modified by: Rhena Inocencio

 ALIASES:

TrojanDownloader:Win32/Xolondox.A (Microsoft); Downloader.a!bnj (McAfee); Trojan.Gen (Symantec); Trojan-Dropper.Win32.Injector.dwrv (Kaspersky); Trojan-Dropper.Win32.Resdro.b (v) (not malicious) (Sunbelt)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 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:

192,960 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

27 Jul 2012

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 drops the following copies of itself into the affected system:

  • %Windows%\Qedie\conime.exe

(Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)

It creates the following folders:

  • %Windows%\Qedie
  • %Windows%\Qedir
  • %User Profile%\Application Data\Storm
  • %User Profile%\Storm\update
  • %User Profile%\update\%SESSIONNAME%

(Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.. %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{AENGFU3AA-B933-11d2-9CBD-0000F87A369E}
stubpath = "%Windows%\Qedie\conime.exe"

It modifies the following registry entries to ensure it automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Shell = "Explorer.exe %Program Files%\Common Files\Microsoft Shared\MSINFO\iejore.exe"

(Note: The default value data of the said registry entry is Explorer.exe.)

Other System Modifications

This Trojan deletes the following files:

  • %User Profile%\%SESSIONNAME%\ftuso.cc3
  • kpmioxdyi
  • %Windows%\cgbgxpwwtd
  • svhglxgfii
  • %System Root%\$temp$
  • %System Root%\Ftp.dll
  • %Windows%\SoftwareDistribution\DataStore\Logs\edbtmp.log

(Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.. %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

It adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{AENGFU3AA-B933-11d2-9CBD-0000F87A369E}

HKEY_LOCAL_MACHINE\sOFtwaRe\kpmioxdyi

HKEY_LOCAL_MACHINE\sOFtwaRe\kpmioxdyin

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Comhidserv70

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Control\MediaResources\msvideo

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
WinOldApp

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Internet Explorer\Control Panel

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\kpmioxdyi
seRVicemAIN = "BuildTrusteeWithSidA"

HKEY_LOCAL_MACHINE\SOFTWARE\kpmioxdyi
seRVicedlL = "%User Profile%\%SESSIONNAME%\ftuso.cc3"

HKEY_LOCAL_MACHINE\SOFTWARE\kpmioxdyi
module = "%Windows%\cgbgxpwwtd"

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Internet Explorer\Control Panel
HomePage = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Window Title = "µã»÷µ¯³öÍøÒ³¹ã¸æ£¬ÓÀ¾Ã¹Ø±Õµ¯³ö´°¿Ú"

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Start Page = "www.yztq.net/article/medicines/info-12934.html"

(Note: The default value data of the said registry entry is http://www.microsoft.com/isapi/redir.dll?prd=ie&pver=6&ar=msnhome.)

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Search Page = "www.yztq.net/article/medicines/info-12934.html"

(Note: The default value data of the said registry entry is http://www.microsoft.com/isapi/redir.dll?prd=ie&ar=iesearch.)

It deletes the following registry keys:

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Active Setup\Installed Components\{AENGFU3AA-B933-11d2-9CBD-0000F87A369E}

Dropping Routine

This Trojan drops the following files:

  • %Program Files%\933.txt
  • %User Temp%\26813985.gif
  • %Windows%\Qedir\hpuaguyq.exe
  • %Windows%\Qedir\eudtqrpv.exe
  • %Windows%\Qedir\ostrlttb.exe
  • %Windows%\Qedir\imindqro.exe
  • %User Temp%\qsgrmpenvn.dat
  • %Windows%\Deleteme.bat
  • %Program Files%\Common Files\Microsoft Shared\MSINFO\Del.bat
  • %Windows%\cgbgxpwwtd
  • %Windows%\QQSAFER.exe
  • %System Root%\$temp$
  • %Program Files%\Common Files\Microsoft Shared\MSINFO\iejore.exe

(Note: %Program Files% is the default Program Files folder, usually C:\Program Files.. %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.. %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.. %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://127.{BLOCKED}0.{BLOCKED}0.1.jk136.com:123/js/js/top.gif
  • http://www.{BLOCKED}u.com.jk136.com:123/js/js/2y.exe
  • http://www.{BLOCKED}u.com.jk136.com:123/js/js/3t.exe
  • http://www.{BLOCKED}u.com.jk136.com:123/js/js/4i.exe
  • http://www.{BLOCKED}u.com.jk136.com:123/js/js/5c.exe
  • http://bbs.{BLOCKED}6.com:123/js/js/90.exe

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.200

FIRST VSAPI PATTERN FILE:

9.288.04

FIRST VSAPI PATTERN DATE:

17 Jun 2012

VSAPI OPR PATTERN File:

9.289.00

VSAPI OPR PATTERN Date:

18 Jun 2012

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Identify and delete files detected as TROJ_DROPR.LFA using either the Startup Disk or Recovery Console

[ Learn More ]

Step 3

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_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components
    • {AENGFU3AA-B933-11d2-9CBD-0000F87A369E}
  • In HKEY_LOCAL_MACHINE\sOFtwaRe
    • kpmioxdyi
  • In HKEY_LOCAL_MACHINE\sOFtwaRe
    • kpmioxdyin
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft
    • Comhidserv70
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\MediaResources
    • msvideo
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies
    • WinOldApp
  • In HKEY_CURRENT_USER\Software\Policies\Microsoft\Internet Explorer
    • Control Panel

Step 4

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_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components\{AENGFU3AA-B933-11d2-9CBD-0000F87A369E}
    • stubpath = "%Windows%\Qedie\conime.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\kpmioxdyi
    • seRVicemAIN = "BuildTrusteeWithSidA"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\kpmioxdyi
    • seRVicedlL = "%User Profile%\%SESSIONNAME%\ftuso.cc3"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\kpmioxdyi
    • module = "%Windows%\cgbgxpwwtd"
  • In HKEY_CURRENT_USER\Software\Policies\Microsoft\Internet Explorer\Control Panel
    • HomePage = "1"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
    • Window Title = "µã»÷µ¯³öÍøÒ³¹ã¸æ£¬ÓÀ¾Ã¹Ø±Õµ¯³ö´°¿Ú"

Step 5

Restore this modified 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\Microsoft\Internet Explorer\Main
    • From: Start Page = "www.yztq.net/article/medicines/info-12934.html"
      To: Start Page = ""http://www.microsoft.com/isapi/redir.dll?prd=ie&pver=6&ar=msnhome""
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
    • From: Search Page = "www.yztq.net/article/medicines/info-12934.html"
      To: Search Page = ""http://www.microsoft.com/isapi/redir.dll?prd=ie&ar=iesearch""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
    • From: Shell = "Explorer.exe %Program Files%\Common Files\Microsoft Shared\MSINFO\iejore.exe"
      To: Shell = ""Explorer.exe""

Step 6

Search and delete these files

[ Learn More ]
There may be some component files 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.
  • %Program Files%\933.txt
  • %User Temp%\26813985.gif
  • %Windows%\Qedir\hpuaguyq.exe
  • %Windows%\Qedir\eudtqrpv.exe
  • %Windows%\Qedir\ostrlttb.exe
  • %Windows%\Qedir\imindqro.exe
  • %User Temp%\qsgrmpenvn.dat
  • %Windows%\Deleteme.bat
  • %Program Files%\Common Files\Microsoft Shared\MSINFO\Del.bat
  • %Windows%\cgbgxpwwtd
  • %Windows%\QQSAFER.exe
  • %System Root%\$temp$
  • %Program Files%\Common Files\Microsoft Shared\MSINFO\iejore.exe

Step 7

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.
  • %Windows%\Qedie
  • %Windows%\Qedir
  • %User Profile%\Application Data\Storm
  • %User Profile%\Storm\update
  • %User Profile%\update\%SESSIONNAME%

Step 8

Scan your computer with your Trend Micro product to delete files detected as TROJ_DROPR.LFA. 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 9

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.

  • %User Profile%\%SESSIONNAME%\ftuso.cc3
  • kpmioxdyi
  • %Windows%\cgbgxpwwtd
  • svhglxgfii
  • %System Root%\$temp$
  • %System Root%\Ftp.dll
  • %Windows%\SoftwareDistribution\DataStore\Logs\edbtmp.log

Step 10

Restore these deleted registry keys/values from backup

*Note: Only Microsoft-related keys/values will be restored. If the malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.

  • In HKEY_CURRENT_USER\SOFTWARE\Microsoft\Active Setup\Installed Components
    • {AENGFU3AA-B933-11d2-9CBD-0000F87A369E}


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