Symantec United States

Symantec AntiVirus Research Center (SARC)
http://www.symantec.com/avcenter
Level 1

W32.Blebla.B.Worm

Discovered on: November 30, 2000

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

W32.Blebla.B.Worm arrives as an email message that has 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 of 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 types of files 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 programs, you see the error message "Windows cannot find Sysrnj.exe. This program is needed for opening files of type 'Application'."

Category: Worm

Virus Definitions: November 30, 2000

Threat Assessment:

Medium Medium Low
Wild:
Medium
Damage:
Medium
Distribution:
Low

Wild:

Damage:

Technical description:

The worm arrives as an email message that has an HTML body and two attachments named Xromeo.exe and Xjuliet.chm. The subject of the email is selected randomly 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 runs only under Windows 95/98/2000 systems that have not had available Microsoft security updates applied. It does not run under Windows NT.

The HTML component in the message causes the attachments to be saved in the \Windows\Temp folder, and launches the Xjuliet.chm file. This file then 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, in order to hide its activity. The virus then 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 MIME-encoded attachments. The virus then 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.

Removal instructions:

To repair the damage done by this worm:

  • Restart the computer in Safe mode.
  • Make sure that Windows is set to show all files.
  • Find and delete the files saved to the hard drive by the worm.
  • At a DOS prompt, copy Regedit.exe to Regedit.com.
  • Edit the registry, and undo the changes made by the worm.

Detailed instructions for each of these steps follow.

To restart the computer in Safe mode:

NOTE: In Safe mode, Windows uses default settings: VGA monitor, no network, Microsoft mouse driver, and the minimum device drivers required to start Windows. You will not have access to CD-ROM drives, printers, or other devices.
  • Windows 95:
      1. Exit all programs.
      2. Click Start, and click Shut Down. The Shut Down Windows dialog box appears.
      3. Click Shut Down, and then click OK.
      4. Click Yes to confirm the shut down.
      5. Turn off the computer (if necessary) and wait 30 seconds.

      NOTE: You must turn off the power to remove the virus from memory. Do not use the reset button.

      6. Turn on the computer.
      7. When you see "Starting Windows 95...," press F8. The Windows 95 Startup Menu appears.
      8. Press the number that corresponds to Safe mode, and press Enter. Windows restarts in Safe mode.
  • Windows 98/Me:
      1. Exit all programs.
      2. Click Start, and click Shut Down. The Shut Down Windows dialog box appears.
      3. Click Shut Down, and then click OK.
      4. Click Yes to confirm the shut down.
      5. Turn off the computer (if necessary) and wait 30 seconds.

      NOTE: You must turn off the power to remove the virus from memory. Do not use the reset button.

      6. Turn on the computer.
      7. During restart, hold down the Ctrl key until the Windows 98 startup menu appears.
      8. Press the number that corresponds to Safe mode, and press Enter. Windows restarts in Safe mode.

To configure Windows to show all files:
    1. Start Windows Explorer.
    2. Click the View menu (Windows 95/98) or the Tools menu (Windows Me), and click Options or Folder Options.
    3. Click the View tab, and uncheck "Hide file extensions for known file types" if it is checked.
    4. Click Show all files, and click OK.

To find the files and folder left by the worm:
    1. Click Start, point to Find, and click Files or Folders. The Find: All files dialog box appears.
    2. Make sure that "Look in" is pointing to drive 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. Windows finds all files and folders that match your search criteria and displays them in the lower pane of the Find dialog box.

    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, all of these files should be deleted. 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, and then click OK to confirm.
    7. In the Named box, type Hi and 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.

To copy Regedit.exe to Regedit.com at a DOS prompt:
1. Click Start, point to Programs, and then click MS-DOS Prompt.
2. Type copy regedit.exe regedit.com and then press Enter.
3. Type start regedit.com and press Enter.
4. Proceed to the To edit the registry section.

NOTE: The Registry Editor opens in front of the DOS window. After you have finished editing the registry and have closed the Registry Editor, close the DOS window as well.

To edit 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. This document is available from the Symantec Fax-on-Demand system. In the U.S. and Canada, call (541) 984-2490, select option 2, and then request document 927002.

If you are confident that you can complete the following steps without error, then please proceed with caution, keeping in mind all warnings you have read.
    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 that is farther down in the list.

    2. In the right pane, double click double-click Default. The Edit String dialog box appears.
    3. Delete the contents of the Value data box, and 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, and then click Yes to confirm.
    7. Click the Edit menu, and click Find.
    8. In the Find what box, type the following and press Enter:

    rnjfile

    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 can be changed by this worm, and their original values (where known) are shown in the following list. You must repeat the search for rnjfile until no more instances of the entry are found in the registry. Press F3 to do so.

    NOTE: This is provided for your convenience. The values on your system may differ from that shown. In some cases, you may need to reinstall the software that is called by the damaged key.

    .arj (The Zip program that 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 that you are using)

    9. Restart the computer, and then run LiveUpdate.


Write-up by: Peter Ferrie