W32.Cone.B@mm

Printer Friendly Page

Discovered: February 29, 2004
Updated: February 13, 2007 12:18:14 PM
Type: Worm
Systems Affected: Windows



W32.Cone.B@mm is a minor variant of W32.Cone@mm . The worm sends itself to the email addresses it gathers from the files on an infected computer. The attachment will have a .exe, .scr, or .zip file extension. The worm also modifies the local hosts file to prevent access to various websites.

Antivirus Protection Dates

  • Initial Rapid Release version February 29, 2004
  • Latest Rapid Release version September 28, 2010 revision 054
  • Initial Daily Certified version February 29, 2004
  • Latest Daily Certified version September 28, 2010 revision 036
  • Initial Weekly Certified release date February 29, 2004

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

Writeup By: Kaoru Hayashi

Discovered: February 29, 2004
Updated: February 13, 2007 12:18:14 PM
Type: Worm
Systems Affected: Windows


When W32.Cone.B@mm runs, it does the following:

  1. Creates the files C:\Debug.A.log and %Windir%\W32.Cyclone.htm. These files do not contain malicious code and you can safely delete them.

  2. Copies itself to the following files:
    • %Windir%\svchost.exe
    • %System%\1enel.dll


      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.
    • %System% is a variable: The worm locates the System folder and copies itself to that location. By default, this is C:\Windows\System (Windows 95/98/Me), C:\Winnt\System32 (Windows NT/2000), or C:\Windows\System32 (Windows XP).

  3. Copies itself as Cyclone.pif into the system-wide and current user's startup folders.

  4. Creates the file, C:\Doc, and opens it with Notepad.exe. Then it deletes the following file, which resembles a Microsoft EULA:




  5. Creates the mutex "C-OnE." This mutex allows only one instance of the worm to execute.

  6. Attempts to stop the AutoProtect Service.

  7. Creates or overwrites the file, %System%\drivers\etc\hosts, with the text:

    127.0.0.1 www.symantec.com
    127.0.0.1 securityresponse.symantec.com
    127.0.0.1 symantec.com
    127.0.0.1 www.sophos.com
    127.0.0.1 sophos.com
    127.0.0.1 www.mcafee.com
    127.0.0.1 mcafee.com
    127.0.0.1 liveupdate.symantecliveupdate.com
    127.0.0.1 www.viruslist.com
    127.0.0.1 viruslist.com
    127.0.0.1 viruslist.com
    127.0.0.1 f-secure.com
    127.0.0.1 www.f-secure.com
    127.0.0.1 kaspersky.com
    127.0.0.1 www.avp.com
    127.0.0.1 www.kaspersky.com
    127.0.0.1 avp.com
    127.0.0.1 www.networkassociates.com|
    127.0.0.1 networkassociates.com
    127.0.0.1 www.ca.com
    127.0.0.1 ca.com
    127.0.0.1 mast.mcafee.com
    127.0.0.1 my-etrust.com
    127.0.0.1 www.my-etrust.com
    127.0.0.1 download.mcafee.com
    127.0.0.1 dispatch.mcafee.com
    127.0.0.1 secure.nai.com
    127.0.0.1 nai.com
    127.0.0.1 www.nai.com
    127.0.0.1 microsoft.com
    127.0.0.1 www.microsoft.com
    127.0.0.1 support.microsoft.com
    127.0.0.1 update.symantec.com
    127.0.0.1 updates.symantec.com
    127.0.0.1 us.mcafee.com
    127.0.0.1 liveupdate.symantec.com
    127.0.0.1 customer.symantec.com
    127.0.0.1 rads.mcafee.com
    127.0.0.1 trendmicro.com
    127.0.0.1 www.trendmicro.com
    127.0.0.1 localhost

  8. If Kazaa is installed, the worm copies itself into the <Kazaa shared folder>\Recieved folder as the following file names:
    • Screensaver-Hot Girls-part%d.scr
    • Winamp5.01.exe
    • BAD-GIRLS(Playboy)-ScreenSaver.scr
    • Playboy-Screensaver-Nov-03.scr

  9. Creates a thread to continuously set the following value:

    "Windows Service Host"="%Windir%\svchost.exe"

    in the registry keys:
    • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

      so that the worm runs when you start Windows.

  10. Scans the following folders for the files that have .mbx, .wab, .html, .eml, .htm, .asp, .shtml, .txt, and .dbx extensions:
    • Internet Cache folder
    • My Documents folder
    • Default profile folder for Mozilla
    • Microsoft Address Book folder
    • Outlook Express folder

      and retrieves email addresses from any files found.

  11. Uses its own SMTP engine to send itself to the email addresses it found in step 10.

    The email has the following characteristics:

    From: (Spoofed)

    Subject: (One of the following)
    • I WILL KILL <name>
    • BREAKING NEWS: US begin the war against IRAN!
    • Thank You <name>!
    • Re: Details (<name>)
    • Password Reset For <name>
    • Undelivered Mail Returned to Sender (<name>)
    • BREAKING NEWS: US begin the war against IRAN!
    • Your account (<name>) will be closed
    • <name>, What you have to say?
    • Mail Delivery System (<name>)
    • Mail Transaction Failed (<name>)
    • WE WANT TO KISS YOU, <name>!
    • WARNING: <name>, WHY YOU TRY TO HACK OUR WEBSITE?

      Attachment Name:
      (One of the following)
    • doc.exe
    • doc.scr
    • pic.exe
    • pic.scr
    • nothing.exe
    • nothing.scr
    • alongtimeago.exe
    • alongtimeago.scr
    • text22F1.exe
    • document.scr
    • untitled.exe
    • CA112732.exe
    • <random>.zip

    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: Kaoru Hayashi

    Discovered: February 29, 2004
    Updated: February 13, 2007 12:18:14 PM
    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. Restore the Hosts file.
    3. Update the virus definitions.
    4. Restart the computer in Safe mode.
    5. Run a full system scan and delete all the files detected as W32.Cone.B@mm.
    6. Delete the value that was 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:
    Note: When you are completely finished with the removal procedure and you are satisfied that the threat has been removed, re-enable 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. Restoring the Hosts file
    The following instructions discuss how to fix the Windows host file so that the added name resolution entries do not prevent you from visiting antivirus vendors' Web sites.
    1. Using Windows Explorer, look for a file named "hosts" in the following locations, if the locations exist:
      • C:\Windows\System32\Drivers\Etc\hosts
      • C:\Winnt\System32\Drivers\Etc\hosts
      • D:\Windows\System32\Drivers\Etc\hosts
      • D:\Winnt\System32\Drivers\Etc\hosts

    2. For each \hosts file that you find, double-click the file.
    3. When the "Open With" dialog box appears, scroll through the list and select Notepad. Do not check the "Always open this program with. . ." box.
    4. Delete the following lines within the file:


      127.0.0.1 www.symantec.com
      127.0.0.1 securityresponse.symantec.com
      127.0.0.1 symantec.com
      127.0.0.1 www.sophos.com
      127.0.0.1 sophos.com
      127.0.0.1 www.mcafee.com
      127.0.0.1 mcafee.com
      127.0.0.1 liveupdate.symantecliveupdate.com
      127.0.0.1 www.viruslist.com
      127.0.0.1 viruslist.com
      127.0.0.1 viruslist.com
      127.0.0.1 f-secure.com
      127.0.0.1 www.f-secure.com
      127.0.0.1 kaspersky.com
      127.0.0.1 www.avp.com
      127.0.0.1 www.kaspersky.com
      127.0.0.1 avp.com
      127.0.0.1 www.networkassociates.com|
      127.0.0.1 networkassociates.com
      127.0.0.1 www.ca.com
      127.0.0.1 ca.com
      127.0.0.1 mast.mcafee.com
      127.0.0.1 my-etrust.com
      127.0.0.1 www.my-etrust.com
      127.0.0.1 download.mcafee.com
      127.0.0.1 dispatch.mcafee.com
      127.0.0.1 secure.nai.com
      127.0.0.1 nai.com
      127.0.0.1 www.nai.com
      127.0.0.1 microsoft.com
      127.0.0.1 www.microsoft.com
      127.0.0.1 support.microsoft.com
      127.0.0.1 update.symantec.com
      127.0.0.1 updates.symantec.com
      127.0.0.1 us.mcafee.com
      127.0.0.1 liveupdate.symantec.com
      127.0.0.1 customer.symantec.com
      127.0.0.1 rads.mcafee.com
      127.0.0.1 trendmicro.com
      127.0.0.1 www.trendmicro.com


      Do not delete the line:

      127.0.0.1 localhost
    5. Save the hosts file.

    3. 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.

    4. Restarting the computer in Safe mode
    Shut down the computer and turn off the power. Wait for at least 30 seconds, and then restart the computer in Safe mode. For instructions, read the document, "How to start the computer in Safe Mode ."


    5. 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 W32.Cone.B@mm, click Delete.

    6. 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 value:

      "Windows Service Host"="%Windir%\svchost.exe"

    5. Repeat steps c and d in the key:

      HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

    6. Exit the Registry Editor.
    7. Restart the computer in Normal mode. For instructions, read the document, "How to start the computer in Safe Mode."



    Writeup By: Kaoru Hayashi