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Internet Security Systems Security Brief 
July 24, 2002

Remote Buffer Overflow Vulnerability in Microsoft Exchange Server

Synopsis:

Microsoft Exchange Server Internet Mail Connector (IMC) provides SMTP
(Simple Mail Transfer Protocol) functionality. It is possible for remote
attackers to formulate a request to trigger a buffer overflow on a
vulnerable Exchange server. This flaw may allow an attacker to either
crash Exchange and block all inbound and outbound email delivery or
allow an attacker to gain complete control of the server.

Impact:

Microsoft Exchange Server is typically exposed to the Internet in order
to send and receive email. Successful exploitation of this vulnerability
can occur through properly configured firewalls. Microsoft Exchange 5.5
is the most heavily deployed version of Exchange on the Internet.
Microsoft reports that over 100 million Exchange licenses have been sold
(http://www.microsoft.com/presspass/Press/2002/Jan02/01-23MarketLeaderPR.
asp).

Affected Versions:

Microsoft Exchange Server version 5.5

For the complete ISS X-Force Security Advisory, please visit:
http://bvlive01.iss.net/issEn/delivery/xforce/alertdetail.jsp?oid=20759
______

About Internet Security Systems (ISS)
Founded in 1994, Internet Security Systems (ISS) (Nasdaq: ISSX) is a
pioneer and world leader in software and services that protect critical
online resources from an ever-changing spectrum of threats and misuse.
Internet Security Systems is headquartered in Atlanta, GA, with
additional operations throughout the Americas, Asia, Australia, Europe
and the Middle East.

Copyright (c) 2002 Internet Security Systems, Inc. All rights reserved
worldwide.

Permission is hereby granted for the electronic redistribution of this
document. It is not to be edited or altered in any way without the
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medium excluding electronic media, please email xforce@iss.net for
permission.

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