Updated Drivers for File and Printer Sharing Security

When you use "File and printer sharing for Microsoft Networks" or "File and printer sharing for NetWare Networks" on a Windows 95-based computer, remote users may be able to gain access to your entire hard disk.

When you share a folder on a Windows 95-based computer, users on UNIX- based computers running the SMBCLIENT Samba network client who connect to the shared folder may be able to gain access to the entire drive on which the shared folder is located.

You may experience this problem with "File and printer sharing for NetWare Networks" or with "File and printer sharing for Microsoft Networks" when the following conditions are met.

File and Printer Sharing for NetWare Networks (Nwserver.vxd):

• Your workstation is configured to share files and printers with "File and printer sharing for NetWare Networks."
• Remote administration or the Microsoft Remote Registry service is enabled.
  
  NOTE: These options are not enabled by default.

File and Printer Sharing for Microsoft Networks (Vserver.vxd):

• Your workstation is configured to share files and printers with "File and printer sharing for Microsoft Networks."
• Your workstation connects to a LAN, Internet (SLIP or PPP account), or Dial-Up Networking connection that can be accessed by UNIX-based computers running the SMBCLIENT Samba network client.
• The network administrator does not disable peer services using System Policies.

The SMBCLIENT Samba network client allows users to send illegal networking commands over the network. At this time, the Samba client is the only known SMBCLIENT that does not filter out such illegal commands. SMBCLIENT users do not automatically gain access to the Windows 95 drive; these users must know the exact steps to send these illegal commands.

To prevent these illegal commands from being run on a Windows 95 computer, Microsoft has released new versions of the Nwserver.vxd (4.00.951) and Vserver.vxd (4.00.952) files. These files are available in the Microsoft Windows 95 Service Pack 1 Update Setup.exe file.

For information about Microsoft Windows 95 Service Pack 1, please see the following article in the Microsoft Knowledge Base:

Installation

To install this update, follow these steps:

1. Download the Setup.exe file from the Microsoft Download Center to an empty folder.
2. In My Computer or Windows Explorer, double-click the Setup.exe file you downloaded in step 1.
3. Follow the instructions on the screen.

The following file is available for download from the Microsoft Download Center:
For additional information about how to download Microsoft Support files, click the following article number to view the article in the Microsoft Knowledge Base: Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help to prevent any unauthorized changes to the file.

This problem is resolved in Microsoft Windows 98.

For additional information about Windows 95 updates, please see the following article in the Microsoft Knowledge Base: