DOCUMENT:Q154174 [crossnet]
TITLE   :Invalid ICMP Datagram Fragments Hang Windows NT, Windows 95   
PRODUCT :Microsoft Windows NT and Windows 95
PROD/VER:3.51 4.00
OPER/SYS:WINDOWS
KEYWORDS:kbbug3.51 kbbug4.00 kbfile kbfix3.51 kbfix4.00 NTSrvWkst nttcp

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The information in this article applies to:

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

Computers running Windows NT or Windows 95 may stop responding (hang) when
they receive corrupt Internet Control Message Protocol (ICMP) datagram
fragments from a client.

RESOLUTION
==========

Microsoft has updated the TCP/IP protocol stack to correct this problem.
Instructions for installing it are available from Microsoft support
channels or directly from the Internet locations below.

Windows NT 4.0
--------------

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/chp/NT40/
   hotfixes-postSP3/icmp-fix

STATUS
======

Microsoft has confirmed this to be a problem in Windows NT versions 3.51
and 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.

Microsoft has confirmed this to be a problem in Microsoft Windows 95 and
OEM Service Release 2 (OSR2). An update to address this problem is now
available, but is not fully regression tested and should be applied only
to computers experiencing this specific problem. Unless you are severely
impacted by this specific problem, Microsoft does not recommend
implementing this update at this time. Contact Microsoft Technical Support
for additional information about the availability of this update.

Additional query words: prodnt 4.00 3.51 win95 ssping spingnuke denial of
service attack hangs

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