DOCUMENT:Q188369  21-APR-1999  [exchange]
TITLE   :XADM: AUTHINFO Command Causes Information Store Problems
PRODUCT :Microsoft Exchange
PROD/VER:WINDOWS:5.0,5.5
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Exchange Server, versions 5.0, 5.5 
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SYMPTOMS
========

A malicious attacker could connect to the NNTP port of an Exchange Server 5.5 or
5.0 machine and disrupt the information store process by issuing specific
sequences of AUTHINFO commands.

When this occurs, an application error similar to one of the following may
occur:

    - The instruction at "0x00611a00" referenced memory at "0x8b4475db". The memory
   could not be "read".

    - The instruction at "0x005cd600" referenced memory at "0x068fb87a". The memory
   could not be "written".

In addition, the Exchange Server information store may stop unexpectedly, causing
the Internet Mail Service and other Exchange Server information services to no
longer function properly.

CAUSE
=====

Improper checking of bounds conditions on certain AUTHINFO command sequences can
result in a buffer overflow.

STATUS
======

Microsoft has confirmed this to be a problem in Microsoft Exchange Server
version 5.0.


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.

This fix has been posted to the following Internet location:

   ftp://ftp.microsoft.com/bussys/exchange/exchange-public/fixes/Eng/Exchg5.0/Post-SP2-STORE/




Microsoft has confirmed this to be a problem in Microsoft Exchange Server version
5.5. This problem has been corrected in the latest U.S. service pack for
Microsoft Exchange Server version 5.5. For information on obtaining the service
pack, query on the following word in the Microsoft Knowledge Base (without the
spaces):

   S E R V P A C K



Additional query words: ims internet mail connector imc

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Keywords          :  
Technology        : kbExchangeSearch kbExchange500 kbExchange550 kbZNotKeyword2
Version           : WINDOWS:5.0,5.5
Issue type        : kbbug
Solution Type     : kbfix

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