VBS.Biscuit.A@mm

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Discovered: September 26, 2003
Updated: February 13, 2007 12:07:57 PM
Also Known As: Worm.Win32.Registra [KAV], VBS/Bisquit [McAfee]
Type: Worm
Systems Affected: Windows


VBS.Biscuit.A@mm is a mass-mailing worm that sends itself as an attachment to the first 50 email addresses in the Microsoft Outlook Address Book.
The email message will have the following characteristics:

Subject : Adsl no problem!!!
Attachments : Adsl_no_problem.pdf<184 spaces>.vbs

The worm attempts to copy itself to both the local host and reachable remote network shares. It will copy itself to the root of the network share as Netlog.vbs.
The worm will also copy the original worm filename to the following folders if it is able to copy netlog.vbs to the root of the share:

  • <network share root>\Windows\Menu Avvio\Programmi\Esecuzione automatica
  • <network share root>\Windows\startm~1\programs\startup
  • <network share root>\Windows
  • <network share root>\Windows\start menu\programs\startup
  • <network share root>\Win95\start menu\programs\startup\
On the 10th of every month, VBS.Biscuit.A@mm will display a pop-up message.

Antivirus Protection Dates

  • Initial Rapid Release version September 26, 2003
  • Latest Rapid Release version September 28, 2010 revision 054
  • Initial Daily Certified version September 26, 2003
  • Latest Daily Certified version September 28, 2010 revision 036
  • Initial Weekly Certified release date October 01, 2003

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

Writeup By: Kevin Ha

Discovered: September 26, 2003
Updated: February 13, 2007 12:07:57 PM
Also Known As: Worm.Win32.Registra [KAV], VBS/Bisquit [McAfee]
Type: Worm
Systems Affected: Windows


When VBS.Biscuit.A@mm is executed, it performs the following actions:

    1. Copies itself as:
      • C:\MyPhoto.JPG.VBS
      • C:\System.dat.vbs
      • C:\Adsl_no_problem.pdf
      • %Windir%\D4NG3.vbs
      • %Windir%\index.html


        Note: %Windir% is a variable. The worm locates the Windows installation folder (by default, this is C:\Windows or C:\Winnt) and copies itself to that location.

    2. Creates the following files:
      • %Windir%\WallPaper.html
      • %Windir%\BasicUpdate.dll.vbs
      • %Windir%\untitled.HTM
      • C:\netlog.tmp
      • C:\Of.txt
      • Script.ini

    3. Adds the values:

      "Data" = "c:\System.dat.vbs"
      "WinMine" = "%Windir%\D4NG3.vbs"
      "WinSetBrowse" = "%Windir%\BasicUpdate.dll.vbs"

      to the registry key:

      HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

      so that the worm runs when you start Windows.

    4. Adds the values:

      "OlkContactRefresh" = "0"
      "OlkFolderRefresh" = "0"
      "FirstRun" = "0"
      "UseOutlook" = "0"

      to the registry key:

      HKEY_CURRENT_USER\Software\Microsoft\WAB\WAB4

    5. Adds the values:

      "Message Send HTML" = "1"
      "Compose Use Stationery" = "1"
      "Stationery Name" = "%Windir%\untitled.HTM"
      "Wide Stationery Name" = "%Windir%\untitled.HTM"

      to the registry key:

      HKEY_CURRENT_USER\Identities\" & %DUID% & "\Software\Microsoft\Outlook Express\5.0\Mail


      Note: %DUID% is a variable. The worm uses the value of the Default User ID in the registry key: HKEY_CURRENT_USER\Identities\Default User ID.

    6. Adds the value:

      "wallPaper" = "%Windir\wallPaper.html"

      to the registry key:

      HKEY_CURRENT_USER\Control Panel\desktop

      so that the desktop displays the following wallpaper:



    7. Adds the value:

      "Start Page" = "http:/ /www.sesso.com"

      to the registry key:

      HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main

      so that the start page of Internet Explorer is set to www.sesson.com.

    8. Adds the values:

      "Account Name" = "mail.supereva.it"
      "Connection Type" = "0"
      "Make Available Offline" = "1"
      "IMAP Port" = "143"
      "IMAP Timeout" = "60"
      "IMAP Use LSUB" = "1"
      "IMAP Polling" = "1"
      "IMAP Svr-side Special Folders" = "1"
      "IMAP Sent Items Folder" = "Posta inviata"
      "IMAP Drafts Folder" = "Bozze"
      "IMAP Prompt for Password" = "0"
      "IMAP Dirty" = "0"
      "IMAP Poll All Folders" = "1"
      "HTTPMail Prompt for Password" = "0"
      "HTTPMail Polling" = "1"
      "ShowAdBar" = "1"
      "POP3 Server" = "mail.supereva.it"
      "POP3 User Name" = "mp3free1"
      "POP3 Password2" = "hex:01 02 6d 00 61 00 69 00 6c 00 2e 00 73 00 75 00 70 00 65 00 72 00 65 00 76 00 61 00 2e 00 69 00 74 00 34 00 42 00 44 00 37 00 31 00 46 00 45 00 30 00 00 00"
      "POP3 Use Sicily" = "0"
      "POP3 Port" = "110"
      "POP3 Timeout" = "60"
      "POP3 Skip Account" = "1"
      "POP3 Prompt for Password" = "0"
      "SMTP Server" = "mail.supereva.it"
      "SMTP Port" = "25"
      "SMTP Timeout" = "60"
      "SMTP Display Name" = "ss dd"
      "SMTP Email Address" = "mp3free1@supereva.it"
      "SMTP Split Messages" = "0"
      "SMTP Split Message Size" = "64"
      "=?SMTP Prompt for Password" = "0"

      to the registry key:

      HKEY_CURRENT_USER\Software\Microsoft\Office\Outlook\OMI Account Manager\Accounts\00000001

      so that it creates a mail account mail.supereva.it in Microsoft Outlook. This may cause an existing mail account to be deleted or overwritten if one exists.

    9. On the 10th of every month, displays the following message:




    10. Searches for files that have these extensions:
      • jpg
      • jpeg
      • dwg
      • bak
      • doc
      • html
      • xls
      • mdb
      • txt
      • mp3
      • gif
      • png
      • htm

        and sets the attributes to Hidden. The worm also copies itself as the same filename and appends .vbs to the filename.

    11. Pings IP addresses from 192.168.0.0 to 255.255.255.255, and, if the host is reachable, copies itself to:
      • <network share root>\Windows\Menu Avvio\Programmi\Esecuzione automatica
      • <network share root>\Windows\startm~1\programs\startup
      • <network share root>\Windows
      • <network share root>\Windows\start menu\programs\startup
      • <network share root>\Win95\start menu\programs\startup\

    12. Searches for C:\Of.txt and sends email messages to the first 50 entries in the Microsoft Outlook Address Book if it does not exist.
      The email message has the following characteristics:

      Subject: Adsl no problem!!!
      Message: <empty>
      Attachments: Adsl_no_problem.pdf <184 spaces>.vbs (13 KB)


      Note: VBS.Biscuit.A@mm may not complete its payload due to a bug in its code. In such cases, an error messge will be displayed.

    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.

    Writeup By: Kevin Ha

    Discovered: September 26, 2003
    Updated: February 13, 2007 12:07:57 PM
    Also Known As: Worm.Win32.Registra [KAV], VBS/Bisquit [McAfee]
    Type: Worm
    Systems Affected: Windows


    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 as VBS.Biscuit.A@mm.
    4. Delete the values that were added to the registry.
    For specific details on each of these steps, read the following instructions.

    1. Disabling 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:
    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. Updating 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: These virus definitions are posted to the LiveUpdate servers once each week (usually on Wednesdays), unless there is a major virus outbreak. To determine whether definitions for this threat are available by LiveUpdate, refer to the Virus Definitions (LiveUpdate).
    • Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted on U.S. business days (Monday through Friday). 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 the Virus Definitions (Intelligent Updater).

      The Intelligent Updater virus definitions are available: Read "How to update virus definition files using the Intelligent Updater" for detailed instructions.

    3. Scanning for and deleting 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 as infected with VBS.Biscuit.A@mm, click Delete.

    4. Deleting the value from the registry


    WARNING: 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 keys only. Read the document, "How to make a backup of the Windows registry ," for instructions.
    1. Click Start, and then click Run. (The Run dialog box appears.)
    2. Type regedit

      Then click OK. (The Registry Editor opens.)

    3. Navigate to the key:

      HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

    4. In the right pane, delete the values:

      "Data" = "c:\System.dat.vbs"
      "WinMine" = "%Windir%\D4NG3.vbs"
      "WinSetBrowse" = "%Windir%\BasicUpdate.dll.vbs"

    5. Navigate to the key:

      HKEY_CURRENT_USER\Software\Microsoft\WAB\WAB4

    6. In the right pane, delete the values:

      "OlkContactRefresh" = "0"
      "OlkFolderRefresh" = "0"
      "FirstRun" = "0"
      "UseOutlook" = "0"

    7. Navigate to the key:

      HKEY_CURRENT_USER\Identities\" & %DUID% & "\Software\Microsoft\Outlook Express\5.0\Mail

    8. In the right pane, delete the values:

      "Message Send HTML" = "1"
      "Compose Use Stationery" = "1"
      "Stationery Name" = "%Windir%\untitled.HTM"
      "Wide Stationery Name" = "%Windir%\untitled.HTM"

    9. Navigate to the key:

      HKEY_CURRENT_USER\Control Panel\desktop

    10. In the right pane, delete the value:

      "wallPaper" = "%Windir\wallPaper.html"

    11. Navigate to the key:

      HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main

    12. In the right pane, delete the value:

      "Start Page" = "http:/ /www.sesso.com"

    13. Navigate to the key:

      HKEY_CURRENT_USER\Software\Microsoft\Office\Outlook\OMI Account Manager\Accounts

    14. In the left pane, delete the subkey:

      "00000001"

    15. Exit the Registry Editor.


    Writeup By: Kevin Ha