DOCUMENT:Q155701
TITLE   :Invalid UDP Frames May Cause WINS to Terminate
PRODUCT :Microsoft Windows NT
PROD/VER:4.00
OPER/SYS:WINDOWS
KEYWORDS:kbbug4.00 kbfile kbfix4.00 kbnetwork ntnetserv NTSrv nttcp

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The information in this article applies to:

 - Microsoft Windows NT Server version 4.0
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SYMPTOMS
========

Invalid UDP frames directed to any computer running WINS raises an
exception in WINS causing it to terminate silently. When WINS is no longer
running, problems such as domain synchronization, browsing, or connectivity
may occur. The event log may contain the following error message:

   Event ID: 4119
   Source  : WINS
   Type    : Error

   Description:

   WINS got a packet that has the wrong format (for example, a label may be
   more than 63 octets).

RESOLUTION
==========

To resolve this problem, obtain the hotfix below, or wait for the next
service pack.

Microsoft has updated Wins.exe to correct this problem. If WINS receives
invalid frames, it logs the event mentioned above but it does not terminate
unexpectedly.

NOTE: Service Pack 3 must be applied to Windows NT 4.0 prior to applying
this fix.

This hotfix has been posted to the following Internet location:

   ftp://ftp.microsoft.com/bussys/winnt/winnt-public/fixes/usa/NT40/
   hotfixes-postSP3/winsupd-fix

STATUS
======

Microsoft has confirmed this to be a problem in Windows NT version 4.0.
A supported fix is now available, but has not been fully regression-tested
and should be applied only to systems experiencing this specific problem.
Unless you are severely impacted by this specific problem, Microsoft
recommends that you wait for the next Service Pack that contains this fix.
Contact Microsoft Technical Support for more information.

Additional query words: 4.00 wins denial of service attack hangs port 137

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