W32.Prolin.Worm

W32.Prolin.Worm uses Microsoft Outlook to email a copy of itself to everyone in the Outlook address book. The worm moves all .mp3, .jpg, and .zip files to the root folder. It renames each of these files and appends the following text to the extension of each file:
change atleast now to LINUX

Also Known As:	TROJ_SHOCKWAVE.A, CREATIVE, TROJ_PROLIN.A
Type:	Worm
Infection Length:	36,864 bytes

Virus Definitions (Intelligent Updater) November 30, 2000

Wild Number of infections: 50 - 999 Number of sites: More than 10 Geographical distribution: Medium Threat containment: Easy Removal: Moderate

Threat Metrics Wild: Medium Damage: Medium Distribution: High

Damage

• Payload:
  • Large scale e-mailing: Emails all addresses in the Outlook address book.
  • Deletes files: Renames and moves all .jpg, .mp3, and .zip files into C:\

Distribution

• Subject of email: A great Shockwave flash movie
• Name of attachment: Creative.exe
• Size of attachment: 36,864
• Target of infection: Win 9x and NT systems.

W32.Prolin.Worm does the following:

1. It uses Microsoft Outlook to email a copy of itself to everyone in the Outlook address book.
   • The attachment is named Creative.exe.
   • The subject of the infected message is
     
     A great Shockwave flash movie.
     
   • The body of the infected message is
     
     Check out this new flash movie that I downloaded just now ... It's Great Bye
     
2. It sends a message to a Yahoo email account.
   • The subject of the message is
     
     Job complete
     
   • The body of the message
     
     Got yet another idiot
     
3. The worm creates a copy of itself with the name Creative.exe in the C:\Windows\Start Menu\Programs\Startup folder. This will run the worm each time you start Windows.
   
   NOTE: It will be able to do this only if C:\Windows is your default Windows folder.
   
4. The worm then moves all .mp3, .jpg, and .zip files to the root folder. It renames each of these files and appends the following text to the extension of each file:
   
   change atleast now to LINUX
   
5. The worm copies the Messageforu.txt file to the root of drive C. The file contains the text
   
   Hi, guess you have got the message. I have kept a list of files that I have infected under this. If you are smart enough just reverse back the process. i could have done far better damage, i could have even completely wiped your harddisk. Remember this is a warning & get it sound and clear... - The Penguin

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.

To remove W32.Prolin.Worm:

1. Find and delete all copies of the Creative.exe file.
2. Open an MS-DOS window and rename the files that were renamed by the worm back to their original extensions.
3. Move the files back to their original locations.

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" or "Search for..." box, type--or copy and paste--the following file name:
   
   creative.exe
   
4. Click Find Now or Search Now.
5. Delete the files that appear in the list.

1. Click Start, point to Programs, and click MS-DOS Prompt or Command Prompt.
2. Type each of the following, and press Enter after each one. Note that there is a space between the second and the third asterisks.
   
   CD\
   ren *.jpg* *.jpg
   ren *.zip* *.zip
   ren *.mp3* *.mp3
   
3. Close the DOS window.

1. Start Windows Explorer.
2. In the left pane select drive C.
3. In the right pane look for the file C:\Messageforu.txt.
   • If it does not exist, skip to step 4.
   • If it does exist:
     1. Double-click the file to open it in Notepad. The file is a list of all files that were moved and renamed, including their original locations.
     2. Use the file as a guide to move the .jpg, and .zip files from the root of drive C to their original locations. To do this, go on to step 4.
4. In the right pane select one of the files that has been moved to the root of drive C, either as indicated by the C:\Messageforu.txt file, or simply because it is a file with the .mp3, .jpg, or .zip extension. Such files should not be stored in the root of drive C.
5. Click Edit, and click Cut.
6. In the left pane, browse to and select the folder to which you want to move the file. This could be the original location as listed in the C:\Messageforu.txt file or a different location of your choice.
7. Click Edit, and click Paste. This moves the file to the new (or original) location.
8. Repeat steps 1 through 7 for all files that must be moved.

Revision History:

• April 4, 2002: Downgraded to Category 2

Write-up by: Cary Ng