Infostealer.Metafisher

SUMMARY

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.

Protection

• Initial Rapid Release version February 17, 2006
• Latest Rapid Release version August 20, 2008 revision 017
• Initial Daily Certified version February 17, 2006 revision 002
• Latest Daily Certified version August 20, 2008 revision 016
• Initial Weekly Certified release date February 22, 2006

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

Threat Assessment

Wild

• Wild Level: Low
• Number of Infections: 0 - 49
• Number of Sites: 0 - 2
• Geographical Distribution: Low
• Threat Containment: Easy
• Removal: Moderate

Damage

• Damage Level: Low

Distribution

• Distribution Level: Low

TECHNICAL DETAILS

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":

• Turn off and remove unneeded services. By default, many operating systems install auxiliary services that are not critical, such as an FTP server, telnet, and a Web server. These services are avenues of attack. If they are removed, blended threats have less avenues of attack and you have fewer services to maintain through patch updates.
• If a blended 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 (for example, all Windows-based computers should have the current Service Pack installed.). Additionally, please apply any security updates that are mentioned in this writeup, in trusted Security Bulletins, or on vendor Web sites.
• 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.
• Configure your email server to block or remove email that contains file attachments that are commonly used to spread viruses, such as .vbs, .bat, .exe, .pif and .scr files.
• Isolate infected computers quickly to prevent further compromising your organization. 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.

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:

• How to disable or enable Windows Me System Restore
• How to turn off or turn on Windows XP System Restore

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.
   • For Norton AntiVirus consumer products: Read the document: How to configure Norton AntiVirus to scan all files.
   • For Symantec AntiVirus Enterprise products: Read the document: How to verify that a Symantec Corporate antivirus product is set to scan all 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.