Q153066: IPC$ Connections Do Not Disconnect

Article: Q153066
Product(s): Microsoft Windows NT
Version(s): 3.5,3.51
Operating System(s): 
Keyword(s): 
Last Modified: 20-FEB-2002

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The information in this article applies to:

- Microsoft Windows NT Server versions 3.5, 3.51 
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SYMPTOMS
========

When a connection is made to a Windows NT 3.51 server to which the user has had
no prior connection, a connection is made to IPC$ as well as to the share. After
disconnecting from the share, the connection to IPC$ remains, as can be seen in
Server Manager under Shares. This may cause concerns for administrators, who may
feel that the connection and any credentials associated with the user who made
the connection might be accessible by someone else using the same computer.

For instance, one company reported the following situation. Administrators needed
to connect to the server from a computer that a user had already logged on to.
The administrator used CONNECT AS to make a connection to the server, downloaded
some files, then disconnected. They noticed that the IPC$ connection was still
there in Server Manager. Their concern was then that the user at that computer
might be able to access the server over that connection with administrator
access.

Additionally, the IPC$ connection is counted by License Manager. As long as the
IPC$ connection is valid, it takes up a license, perhaps preventing other users
from connecting to a resource.

This connection will drop off when autodisconnect runs (after 15 minutes of
inactivity by default).

RESOLUTION
==========

This does not pose a security concern, as explained below (under MORE
INFORMATION). However, license counts by License Manager are a valid concern.
One instant solution is to turn off the License Logging service, using the
Services tool in Control Panel.

The problem has been corrected in Windows NT 4.0. The IPC$ connection is dropped
immediately after user validation.


MORE INFORMATION
================

Server Manager will show the connection user as the user's name while the share
connection is maintained. If the user disconnects from the share, then the IPC$
connection user will change to the user's computer name. At this point, any user
at that computer attempting to connect will have to authenticate with the
server. Although the IPC$ connection is still intact, it is not associated with
any user name or credentials, so it does not pose a security risk.

Additional query words: 3.50 3.51

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Keywords          :  
Technology        : kbWinNTsearch kbWinNT351search kbWinNT350search kbWinNTSsearch kbWinNTS351 kbWinNTS350 kbWinNTS351search kbWinNTS350search
Version           : :3.5,3.51

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