W32.Blebla.B.Worm

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Discovered: November 30, 2000
Updated: February 13, 2007 11:33:08 AM
Also Known As: I-Worm.Blebla.b [KAV], W32/BleBla.b@MM [McAfee], WORM_BLEBLA.B [Trend], W32/Verona-B [Sophos], Win32.Verona.B [CA]
Type: Worm
Systems Affected: Windows


The W32.Blebla.B.Worm is a minor update of the original W32.Blebla worm. The file names have been changed to Xromeo.exe and Xjuliet.chm, perhaps to avoid detection based only on the file names.

W32.Blebla.B.Worm arrives as an email message, with an HTML body and two attachments named Xromeo.exe and Xjuliet.chm. When you read the message, the two attachments are automatically saved and launched. When launched, the worm attempts to send itself to all the names in the Microsoft Outlook address book and post messages to the alt.comp.virus newsgroup. The worm also alters registry keys, so that it is run when certain file types are viewed or executed.

The following files are saved to the hard disk:

  • Xromeo.exe
  • Xjuliet.chm
  • 001.txt
  • 002.txt
  • Sysrnj.exe

If you quarantine the Sysrnj.exe file and then attempt to start the programs, you see the error message, "Windows cannot find Sysrnj.exe. This program is required for opening files of type 'Application'."

Antivirus Protection Dates

  • Initial Rapid Release version November 30, 2000
  • Latest Rapid Release version August 08, 2016 revision 023
  • Initial Daily Certified version November 30, 2000
  • Latest Daily Certified version August 09, 2016 revision 001
  • Initial Weekly Certified release date November 30, 2000

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

Writeup By: Peter Ferrie

Discovered: November 30, 2000
Updated: February 13, 2007 11:33:08 AM
Also Known As: I-Worm.Blebla.b [KAV], W32/BleBla.b@MM [McAfee], WORM_BLEBLA.B [Trend], W32/Verona-B [Sophos], Win32.Verona.B [CA]
Type: Worm
Systems Affected: Windows


The worm arrives as an email message, with an HTML body and two attachments named Xromeo.exe and Xjuliet.chm. The subject of the email is randomly selected from the following set:

  • Romeo&Juliet
  • where is my juliet ?
  • where is my romeo ?
  • hi
  • last wish ???
  • lol :)
  • ,,...
  • !!!
  • newborn
  • merry christmas!
  • surprise !
  • Caution: NEW VIRUS !
  • scandal !
  • ^_^
  • Re:

This worm should run only under Windows 95/98/Me/2000 systems that have not had applied available Microsoft security updates. It does not run under Windows NT. There have been unconfirmed reports that the worm has been found on computers running Windows XP. The version of Internet Explorer that comes with this operating systems should already have all the required Microsoft security patches. If you think your Windows XP computer is infected with this worm, follow the instructions in the "Removal" section later in the writeup.

NOTES :
The HTML component in the message causes the attachments to be saved in the \Windows\Temp folder and launches the Xjuliet.chm file. Then, this file launches the Xromeo.exe file, which is the mass-mailer component of the worm.

The Xromeo.exe file attempts to terminate the HH.exe process to hide its activity. Then, the virus queries the Outlook Address Book and tries to propagate itself using several different mail servers with these IP addresses:
  • 195.117.117.6
  • 212.244.197.164
  • 195.205.96.185
  • 195.116.104.14
  • 195.117.3.111
  • 195.116.221.65
  • 212.244.67.20
  • 194.181.138.141
  • 195.205.121.183
  • 195.117.88.7
  • 212.160.95.1
  • 212.244.241.81
  • 195.205.208.33
  • 212.106.133.133
  • 195.116.72.5
  • 213.25.175.3
  • 195.117.99.98
  • 213.25.111.2

The virus has its own email engine. It connects to one of the above servers and tries to send its email message with the MIME-encoded attachments. Then, the virus alters the following registry keys to point to a file called Sysrnj.exe in the Windows directory:
  • .exe
  • .jpg
  • .jpeg
  • .jpe
  • .bmp
  • .gif
  • .avi
  • .mpg
  • .mpeg
  • .wmf
  • .wma
  • .wmv
  • .mp3
  • .mp2
  • .vqf
  • .doc
  • .xls
  • .zip
  • .rar
  • .lha
  • .arj
  • .reg

When a file with any of these extensions is launched, the worm will move the file into C:\Recycled under a random file name and replace the original file with itself, adding .exe to the suffix. For example, song.mp3 will become song.mp3.exe, and this file will be the worm. The original file is not executed.

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: Peter Ferrie

Discovered: November 30, 2000
Updated: February 13, 2007 11:33:08 AM
Also Known As: I-Worm.Blebla.b [KAV], W32/BleBla.b@MM [McAfee], WORM_BLEBLA.B [Trend], W32/Verona-B [Sophos], Win32.Verona.B [CA]
Type: Worm
Systems Affected: Windows


These instructions are for all the current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.

  1. Restart the computer in Safe mode.
  2. Copy Regedit.exe to Regedit.com.
  3. Edit the registry and undo the changes made by the worm.
  4. Configure Windows to show all the files.
  5. Find and delete the files saved to the hard drive by the worm.
  6. Restart in Normal mode.
  7. Update the virus definitions.
  8. Run a full system scan and delete all the files detected as W32.Blebla.B.Worm.

For details on how to do this, read the following instructions.

Restarting the computer in Safe mode
All Windows 32-bit operating systems, except Windows NT, can be restarted in Safe mode. For instructions on how to do this, read the document, "How to start the computer in Safe Mode ."

Copying Regedit.exe to Regedit.com
Because the worm modified the registry so that you cannot run the .exe files, first make a copy of the Registry Editor as a file with the .com extension, then run the file.
  1. Do one of the following, depending on which version of Windows you are running:
    • Windows 95/98 users:
      1. Click Start.
      2. Point to Programs.
      3. Click the MS-DOS Prompt. (A DOS window opens at the C:\Windows prompt.) Proceed to step 2 of this section.
    • Windows Me users:
      1. Click Start.
      2. Point to Programs.
      3. Point to Accessories.
      4. Click the MS-DOS Prompt. (A DOS window opens at the C:\Windows prompt.) Proceed to step 2 of this section.
    • Windows NT/2000 users:
      1. Click Start, then click Run.
      2. Type command, then press Enter. (A DOS window opens.)
      3. Type cd \winnt, then press Enter.
      4. Go to step 2 of this section.
    • Windows XP users:
      1. Click Start, then click Run.
      2. Type command, then press Enter. (A DOS window opens.)
      3. Type the following:

        cd\
        cd \windows

        Then press Enter after typing each one.
      4. Proceed to step 2 of this section.
  2. Type copy regedit.exe regedit.com, then press Enter.
  3. Type start regedit.com, then press Enter. (The Registry Editor will open in front of the DOS window.)

Editing the registry

CAUTION : We strongly recommend that you back up the system registry before making any changes to it. Incorrect changes to the registry may result in permanent data loss or corrupted files. Be sure to modify the specified keys only. See the document, "How to back up the Windows registry ," before proceeding.
  1. Navigate to and open the following key:

    HKEY_CLASSES_ROOT\.exe

    CAUTION: Make sure that you go to the .exe subkey (note the period) and not the exefile subkey, which is farther down in the list.
  2. In the right pane, double-click Default. (The Edit String dialog box appears.)
  3. Delete the contents of the Value data box, then type: exefile.
  4. Click OK. The key should now look like this:



  5. Navigate to and select the following key: HKEY_CLASSES_ROOT\rnjfile.

    NOTE: In this case, there is no period before the first letter.
  6. Press Delete, then click Yes to confirm.
  7. Click the Edit menu and click Find.
  8. In the Find what box, type rnjfile and press Enter


    You must change any resultant entries to the correct settings. Entries will be found in many keys. These key names begin with a period. You must edit the Default value for each key to change it back to the correct setting. Some of the keys that the worm can change, as well as their original values (when known) are shown in the following list. Repeat the search for rnjfile until more instances of the entry are not found in the registry. Press F3 to do so.

    NOTE: This list is provided for your convenience. The values on your system may differ from those listed. In some cases, you may need to re-install the software called by the damaged key.

    .arj (The Zip program you are using)
    .avi AVIFile
    .bmp Paint.Picture
    .doc (Double-click the .doc subkey and change the Default value to reflect the latest version of Word; for example, Word.Document.8.)
    .gif giffile
    .jpeg jpegfile
    .jpe
    .jpg jpegfile
    .lha
    .mp2 mpegfile
    .mp3 mp3file
    .mpeg mpegfile
    .mpg mpegfile
    .rar
    .reg regfile
    .vqf
    .wma
    .wmf
    .wmv
    .xls (Double-click the .doc subkey and change the Default value to reflect the latest version of Excel; for example, Excel.Sheet.8.)
    .zip (The Zip program you are using)
  9. Exit the Registry Editor and close the remaining DOS window.
  10. Restart the computer, then run LiveUpdate.

Configuring Windows to show all the files
  1. Start Windows Explorer.
  2. Click the View menu (Windows 95/98/NT) or the Tools menu (Windows Me/2000/XP), then click the Options or Folder options.
  3. Click the View tab.
  4. Uncheck "Hide file extensions for known file types."
  5. Do one of the following:
    • Windows 95/NT: Click "Show all files."
    • Windows 98: In the Advanced settings box, under the "Hidden files" folder, click Show all files.
    • Windows Me/2000/XP: Uncheck "Hide protected operating system files," and under the "Hidden files" folder, click "Show hidden files and folders."
  6. Click Apply, then click OK.

Finding the files and folder left by the worm
  1. Click Start, point to Find or Search, and click Files or Folders.
  2. Make sure that "Look in" is set to (C:) and that Include subfolders is checked.
  3. In the Named box, type, or copy and paste, the following text:

    sysrnj*.* xromeo*.* xjuliet*.* 001.txt 002.txt
  4. Click Find Now. The results are displayed.

    NOTE: In the next step, you will be directed to delete the resultant files. In most cases, these files will include Xromeo.exe, Xjuliet.chm, and Sysrnj.exe. If you have a minor variant, or if the worm has run more than once, the files could have slightly different names, such as Xromeo.lgc, Xromeo(1).exe, Xjuliet(1).chm, and so on. In most cases, you should delete all these files. If you think that the file could be a legitimate program file, because the file name differs substantially, we suggest that you first record the location of the file, and then copy the file to a clearly marked floppy disk before you delete it.
  5. Delete each file, clicking Yes to confirm its deletion.
  6. Click New Search, then click OK to confirm.
  7. In the Named box, type Hi, then click Find Now.
  8. If a folder named Hi is found, delete it.
  9. Close the Find Files window.
  10. Right-click the Recycle bin icon on the Windows desktop and click Empty Recycle Bin.

Restarting in Normal mode
Restart the computer and allow it to start as you normally would.

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 the 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), in the "Protection" section, at the top of this writeup.
  • 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), in the "Protection" section, at the top of this writeup.

    The Intelligent Updater virus definitions are available here. For detailed instructions on how to download and install the Intelligent Updater virus definitions from the Symantec Security Response Web site, click here.

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.Blebla.B.Worm, click Delete.


Writeup By: Peter Ferrie