Infostealer.Metafisher

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Discovered: February 16, 2006
Updated: February 13, 2007 12:53:58 PM
Also Known As: Trojan-PSW.Win32.Agent.{eo, ey, fg, fl} [Kaspersky Lab], Spy-Agent.ak [McAfee], Troj/PWS-{EC, EJ} [Sophos], TSPY_AGENT.{AMD, BGN} [Trend Micro]
Type: Trojan Horse
Systems Affected: Windows



Infostealer.Metafisher is a Trojan horse that exploits the Microsoft Windows Graphics Rendering Engine WMF Format Unspecified Code Execution Vulnerability (as described in Microsoft Security Bulletin MS06-001 ) to download remote files. The Trojan also sends bank account and personal information to remote servers.

Note: Virus definitions dated prior to February 17, 2006 may detect this as Download.Trojan.

Antivirus Protection Dates

  • Initial Rapid Release version February 17, 2006
  • Latest Rapid Release version November 04, 2019 revision 019
  • Initial Daily Certified version February 17, 2006 revision 002
  • Latest Daily Certified version November 04, 2019 revision 065
  • Initial Weekly Certified release date February 22, 2006

Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.


Technical Description


The Trojan was spammed out as one of the following emails:

From: Dell Online Store
Subject: Its order #76453 to total of 739,00$ was accepted
Message Body:
We thank for to You a purchase to him with our company.
Its No76453 order for Panasonic Digital Lt-j28 7,0 MP Double bed to total
of 739,00$ was accepted.
Its banking letter will be included in that amount.
We thank for its purchase to him.
You can verify your order in your Parametros of the User
Tighten here to see its order
Very kindly,
Dell Online Store

From: Sunrise Online Store
Subject: Su orden #F8A2198CD8E a total de 576.00$ fue acceptado
Message Body:
Le agradecemos a Ud una compra con nuestra empresa.
Su orden No F8A2198CD8E para Sony RX-F18 8.0 MP
Digital Camera a total de 576.00$ fue acceptado.
Su carta bancaria se incluira' en aquel importe.
Le agradecemos su compra.
Ud puede comprobar su orden en sus Parametros del
Usuario
Aprete aqui para ver su orden
Muy atentamente,
Sunrise Online Store

If the link contained in the email is clicked, the following the browser will connect to one of the following domains:

  • [http://]advanced-customers-online.com/[REMOVED]
  • [http://]frandenburg-online.com/[REMOVED]

These domains contain the file XPL.WMF, which exploits the Microsoft Windows Graphics Rendering Engine WMF Format Unspecified Code Execution Vulnerability (BID 16047) to download and execute the following remote file:
1.exe

When this file is executed, it performs the following actions:
  1. Modifies the values:

    "(Default)" = ":*:MCAFEE_SIGNATURE_HERE_LOL"
    "%ProgramFiles%\Internet Explorer\IEXPLORE.EXE" = "%ProgramFiles%\Internet Explorer\IEXPLORE.EXE:*:Enabled:Internet Explorer"

    in the registry subkey:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\
    SharedAccess\Parameters\FirewallPolicy\StandardProfile\
    AuthorizedApplications\List

    to allow it access through the Windows Firewall.

    Note: %ProgramFiles% is a variable that refers to the program files folder. By default, this is C:\Program Files.

  2. Downloads the following file:

    installer.exe

  3. Attempts to create the following files:

    • C:\djrgjeigjeoirgjerirg.txt
    • C:\zzzzzzzzzzzzzzzzzzzzzzz222

  4. Adds the values:

    "next_install" = "420ca762"
    "compid" = "[RANDOM_ID]"

    to the registry subkey:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Control Panel\load

  5. Adds the value:

    "Enable Browser Extensions" = "yes"

    to the registry subkey:

    HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main

  6. Creates of the following registry subkeys:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Control Panel\load\httpreport
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Control Panel\load\waspopup
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Control Panel\load\formwas
    HKEY_LOCAL_MACHINE\SOFTRWARE\Microsoft\Windows\CurrentVersion\Explorer\
    Browser Helper Objects\{78364D99-A640-4DDF-B91A-67EFF8373045}

  7. Creates the following .dll file and registers it as a Browser Helper Object:

    %System%\msnscps.dll

    Note: %System% is a variable that refers to the System folder. By default this is C:\Windows\System (Windows 95/98/Me), C:\Winnt\System32 (Windows NT/2000), or C:\Windows\System32 (Windows XP).

  8. Once installed the Trojan will create the following files:

    • %System%\form.txt
    • %System%\info.txt
    • %System%\shot.html

      Note: These files are used to store stolen information from the compromised computer.

  9. Gather the following information:

    • Host name and IP address
    • Outlook Express accounts
    • SMTP / POP3 server
    • Passwords for Internet Explorer's AutoComplete feature
    • MSN Explorer accounts
    • Windows cached passwords
    • URLs visited
    • HTTP POST requests
    • Content of HTTP FORM

  10. May display the following message when the user opens Internet Explorer:




    Title:
    Microsoft Visual C++ Runtime Library
    Body:
    Program Error!
    Program: C:\Program Files\Internet Explorer\IEXPLORE.exe
    This application has requested the Runtime to terminate it in an unusual
    way.
    Please contact the application's support team for more information.

  11. Creates the file C:\1.bat, which contains commands do delete system files in the following locations:
    • C:\*.*
    • %SystemDrive%
    • %ProgramFiles%

      Note:
    • This routine that can be activated by the remote attacker to destroy data on the compromised computer.
    • %SystemDrive% is a variable that refers to the drive on which Windows is installed. By default, this is drive C.

  12. May contact the following remote host:

    [http://]european-business-organization.com/[REMOVED]/chat.php

  13. Can be remotely configured to send all the gathered information to a remote host using the HTTP or FTP protocol.


Recommendations

Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":

  • Use a firewall to block all incoming connections from the Internet to services that should not be publicly available. By default, you should deny all incoming connections and only allow services you explicitly want to offer to the outside world.
  • Enforce a password policy. Complex passwords make it difficult to crack password files on compromised computers. This helps to prevent or limit damage when a computer is compromised.
  • Ensure that programs and users of the computer use the lowest level of privileges necessary to complete a task. When prompted for a root or UAC password, ensure that the program asking for administration-level access is a legitimate application.
  • Disable AutoPlay to prevent the automatic launching of executable files on network and removable drives, and disconnect the drives when not required. If write access is not required, enable read-only mode if the option is available.
  • Turn off file sharing if not needed. If file sharing is required, use ACLs and password protection to limit access. Disable anonymous access to shared folders. Grant access only to user accounts with strong passwords to folders that must be shared.
  • Turn off and remove unnecessary services. By default, many operating systems install auxiliary services that are not critical. These services are avenues of attack. If they are removed, threats have less avenues of attack.
  • If a threat exploits one or more network services, disable, or block access to, those services until a patch is applied.
  • Always keep your patch levels up-to-date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
  • Configure your email server to block or remove email that contains file attachments that are commonly used to spread threats, such as .vbs, .bat, .exe, .pif and .scr files.
  • Isolate compromised computers quickly to prevent threats from spreading further. Perform a forensic analysis and restore the computers using trusted media.
  • Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses. Simply visiting a compromised Web site can cause infection if certain browser vulnerabilities are not patched.
  • If Bluetooth is not required for mobile devices, it should be turned off. If you require its use, ensure that the device's visibility is set to "Hidden" so that it cannot be scanned by other Bluetooth devices. If device pairing must be used, ensure that all devices are set to "Unauthorized", requiring authorization for each connection request. Do not accept applications that are unsigned or sent from unknown sources.
  • For further information on the terms used in this document, please refer to the Security Response glossary.


Removal


The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.

  1. Disable System Restore (Windows Me/XP).
  2. Update the virus definitions.
  3. Run a full system scan and delete all the files detected.
  4. Delete any values added to the registry.
For specific details on each of these steps, read the following instructions.

1. To disable System Restore (Windows Me/XP)
If you are running Windows Me or Windows XP, we recommend that you temporarily turn off System Restore. Windows Me/XP uses this feature, which is enabled by default, to restore the files on your computer in case they become damaged. If a virus, worm, or Trojan infects a computer, System Restore may back up the virus, worm, or Trojan on the computer.

Windows prevents outside programs, including antivirus programs, from modifying System Restore. Therefore, antivirus programs or tools cannot remove threats in the System Restore folder. As a result, System Restore has the potential of restoring an infected file on your computer, even after you have cleaned the infected files from all the other locations.

Also, a virus scan may detect a threat in the System Restore folder even though you have removed the threat.

For instructions on how to turn off System Restore, read your Windows documentation, or one of the following articles:
Note:
When you are completely finished with the removal procedure and are satisfied that the threat has been removed, reenable System Restore by following the instructions in the aforementioned documents.

For additional information, and an alternative to disabling Windows Me System Restore, see the Microsoft Knowledge Base article: Antivirus Tools Cannot Clean Infected Files in the _Restore Folder (Article ID: Q263455).

2. To update the virus definitions
Symantec Security Response fully tests all the virus definitions for quality assurance before they are posted to our servers. There are two ways to obtain the most recent virus definitions:
  • Running LiveUpdate, which is the easiest way to obtain virus definitions:
    • If you use Norton AntiVirus 2006, Symantec AntiVirus Corporate Edition 10.0, or newer products, LiveUpdate definitions are updated daily. These products include newer technology.
    • If you use Norton AntiVirus 2005, Symantec AntiVirus Corporate Edition 9.0, or earlier products, LiveUpdate definitions are updated weekly. The exception is major outbreaks, when definitions are updated more often.
  • Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted daily. You should download the definitions from the Symantec Security Response Web site and manually install them. To determine whether definitions for this threat are available by the Intelligent Updater, refer to Virus Definitions (Intelligent Updater).

    The latest Intelligent Updater virus definitions can be obtained here: Intelligent Updater virus definitions. For detailed instructions read the document: How to update virus definition files using the Intelligent Updater.

3. To scan for and delete the infected files
  1. Start your Symantec antivirus program and make sure that it is configured to scan all the files.
  2. Run a full system scan.
  3. If any files are detected, click Delete.

Important: If you are unable to start your Symantec antivirus product or the product reports that it cannot delete a detected file, you may need to stop the risk from running in order to remove it. To do this, run the scan in Safe mode. For instructions, read the document, How to start the computer in Safe Mode . Once you have restarted in Safe mode, run the scan again.

After the files are deleted, restart the computer in Normal mode and proceed with the next section.

Warning messages may be displayed when the computer is restarted, since the threat may not be fully removed at this point. You can ignore these messages and click OK. These messages will not appear when the computer is restarted after the removal instructions have been fully completed. The messages displayed may be similar to the following:

Title: [FILE PATH]
Message body: Windows cannot find [FILE NAME]. Make sure you typed the name correctly, and then try again. To search for a file, click the Start button, and then click Search.


4. To delete the value from the registry
Important: Symantec strongly recommends that you back up the registry before making any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify the specified subkeys only. For instructions refer to the document: How to make a backup of the Windows registry.
  1. Click Start > Run.
  2. Type regedit
  3. Click OK.

    Note: If the registry editor fails to open the threat may have modified the registry to prevent access to the registry editor. Security Response has developed a tool to resolve this problem. Download and run this tool, and then continue with the removal.

  4. Navigate to the subkey:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\
    SharedAccess\Parameters\FirewallPolicy\StandardProfile\
    AuthorizedApplications\List

  5. In the right pane, delete the values:

    "(Default)" = ":*:MCAFEE_SIGNATURE_HERE_LOL"
    "%ProgramFiles%\Internet Explorer\IEXPLORE.EXE" = "%ProgramFiles%\Internet Explorer\IEXPLORE.EXE:*:Enabled:Internet Explorer"

  6. Navigate to the subkey:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Control Panel\load

  7. In the right pane, delete the values:

    "next_install" = "420ca762"
    "compid" = "[RANDOM_ID]"

  8. Navigate to the subkey:

    HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main

  9. In the right pane, delete the value:

    "Enable Browser Extensions" = "yes"

  10. Delete the registry subkeys:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Control Panel\load\httpreport
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Control Panel\load\waspopup
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Control Panel\load\formwas
    HKEY_LOCAL_MACHINE\SOFTRWARE\Microsoft\Windows\CurrentVersion\Explorer\
    Browser Helper Objects\{78364D99-A640-4DDF-B91A-67EFF8373045}

  11. Exit the Registry Editor.


Writeup By: Elia Florio