W32.Music.E.Worm

SUMMARY

W32.Music.E.Worm is a worm that runs only on Windows 95 and Windows 98 computers. The worm requires a specific Win32 API that is only available in Windows 95 and Windows 98 versions of Kernel32.dll.

Protection

• Virus Definitions (Intelligent Updater) November 27, 2000

Threat Assessment

Wild

• Wild Level: Medium
• Number of Infections: 50 - 999
• Number of Sites: More than 10
• Geographical Distribution: Medium
• Threat Containment: Moderate
• Removal: Moderate

Damage

• Damage Level: Low
• Modifies Files: Windows registry

Distribution

• Distribution Level: Medium
• Subject of Email: Variable
• Name of Attachment: Variable (usually Music.com)
• Size of Attachment: 39,936 bytes

TECHNICAL DETAILS

W32.Music.E.Worm is a variant of W32.Music.A.Worm. The main difference between the two is that W32.Music.E.Worm goes to a different Web site to download the mailer component. This new dropper component does not necessarily depend on a specific mailer component; that is, it may work with any version of the mailer component. The result is that the subject and body of the message to which the file is attached may vary, as well as the name of the attachment.

Recommendations

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.

REMOVAL

To remove W32.Music.E.Worm:

• Remove the registry entries made by the worm.
• Delete the file added by the worm.
• Run a full system scan and delete any infected files.

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.

1. Click Start, and click Run. The Run dialog box appears.
2. Type regedit and then click OK. The Registry Editor opens.
3. Navigate to and select the following subkey:
   
   HKEY_LOCAL_MACHINESOFTWAREMicrosoftMCM
   
4. Press Delete, and then click Yes to confirm.
5. Navigate to and select the following subkey:
   
   HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows CurrentVersionRun
   
6. In the right pane, select the following value:
   
   SysDrv c:windowssystemsysmcm.exe
   
7. Press Delete, and then click Yes to confirm.
8. Exit the Registry Editor.

To delete the file:

1. Click Start, point to Find, 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 the following and then click Find Now:
   
   sysmcm.exe
   
4. Windows will find the file and display it in the lower pane of the Find dialog box. It should be located in the WindowsSystem folder.
5. Select the file, press Delete, and then click Yes to confirm.
6. Close the Find Files window.
7. Right-click the Recycle Bin icon on your desktop, and click Empty Recycle Bin.

To scan for infected files:

1. Start Norton AntiVirus (NAV), and then run a full system scan. Unless you are using NAV 2001, make sure that NAV is set to scan all files.
2. Delete any files that are detected as infected with W32.Music.E.Worm.