-----BEGIN PGP SIGNED MESSAGE-----

===========================================================================
             AUSCERT External Security Bulletin Redistribution

           ESB-2003.0182 -- Microsoft Security Bulletin MS03-007
  Unchecked buffer in Windows component could cause webserver compromise
                                 (815021)
                               19 March 2003

===========================================================================

        AusCERT Security Bulletin Summary
        ---------------------------------

Product:                IIS 5.0
                        WebDAV
Vendor:                 Microsoft
Operating System:       Windows 2000
Impact:                 Administrator Compromise
Access Required:        Remote
CVE Id:                 CAN-2003-0109

Ref:                    AL-2003.02
                        ESB-2003.0175

- --------------------------BEGIN INCLUDED TEXT--------------------

- -----BEGIN PGP SIGNED MESSAGE-----

- - -----------------------------------------------------------------
Title:      Unchecked buffer in Windows component could cause web 
            server compromise (815021)
Date:       17 March, 2003
Software:   Microsoft Windows 2000
Impact:     Run Code of Attacker's Choice 
Max Risk:   Critical
Bulletin:   MS03-007

Microsoft encourages customers to review the Security Bulletins 
at: 
http://www.microsoft.com/technet/security/bulletin/MS03-007.asp
http://www.microsoft.com/security/security_bulletins/ms03-007.asp
- - -----------------------------------------------------------------

Issue:
======
Microsoft Windows 2000 supports the World Wide Web Distributed 
Authoring and Versioning (WebDAV) protocol. WebDAV, defined in 
RFC 2518, is a set of extensions to the Hyper Text Transfer 
Protocol (HTTP) that provide a standard for editing and file 
management between computers on the Internet. A security 
vulnerability is present in a Windows component used by WebDAV, 
and results because the component contains an unchecked buffer.

An attacker could exploit the vulnerability by sending a 
specially formed HTTP request to a machine running Internet 
Information Server (IIS). The request could cause the server to 
fail or to execute code of the attacker's choice. The code would 
run in the security context of the IIS service (which, by 
default, runs in the LocalSystem context).

Although Microsoft has supplied a patch for this vulnerability 
and recommends customers install the patch immediately, 
additional tools and preventive measures have been provided that 
customers can use to block the exploitation of this vulnerability 
while they are assessing the impact and compatibility of the 
patch. These temporary workarounds and tools are discussed in the 
"Workarounds" section in the FAQ below. 


Mitigating Factors:
====================
 - URLScan, which is a part of the IIS Lockdown Tool will block 
this attack in its default configurations 
 - The vulnerability can only be exploited remotely if an 
attacker can establish a web session with an affected server 

Risk Rating:
============
 - Critical

Patch Availability:
===================
 - A patch is available to fix this vulnerability. Please read 
the Security Bulletins at

http://www.microsoft.com/technet/security/bulletin/ms03-007.asp
http://www.microsoft.com/security/security_bulletins/ms03-007.asp

   for information on obtaining this patch.


- - -----------------------------------------------------------------

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS 
PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT 
DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING 
THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS 
BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, 
INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL 
DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN 
ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT 
ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL 
OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.

- -----BEGIN PGP SIGNATURE-----
Version: PGP 7.1

iQEVAwUBPnYUXY0ZSRQxA/UrAQG43Af/d+IndquMNQlQLS2LjEFwBy5bh+np051f
fu65SMf6L5owLobpzMvprwKtqSVdLLco3ynyi76Vq4VG52suh1ft+B7AbVNaKEkG
///qWiBQThiTTIw5qwgW+x7h/O6bvIKUvK1O/LdU8WGpph7ZCInA2dSXxo4hwJyM
J4UJeKNtGc4VqcTZzI11q+ebgy5q3XEjDep89H49D836h0hRJywZzzD4pgm/YtFg
JpARG9nkrUEj50cVKEPTggBaHVMxV7agJL7XrmytelXa4yUUia8r7R0SdpNTJc0X
FO5daVtgx6hIY22ryRlPumqQ7K40Z5iBhfd1hHNpPvasucj++/ytKQ==
=e404
- -----END PGP SIGNATURE-----

- --------------------------END INCLUDED TEXT--------------------

You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to auscert@auscert.org.au
and we will forward your request to the appropriate person.

This security bulletin is provided as a service to AusCERT's members.  As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content.  The decision to use any or all of this information is
the responsibility of each user or organisation, and should be done so in
accordance with site policies and procedures.

NOTE: This is only the original release of the security bulletin.  It may
not be updated when updates to the original are made.  If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.

Contact information for the authors of the original document is included
in the Security Bulletin above.  If you have any questions or need further
information, please contact them directly.

Previous advisories and external security bulletins can be retrieved from:

        http://www.auscert.org.au/render.html?cid=1980

If you believe that your system has been compromised, contact AusCERT or
your representative in FIRST (Forum of Incident Response and Security
Teams).

Internet Email: auscert@auscert.org.au
Facsimile:      (07) 3365 7031
Telephone:      (07) 3365 4417 (International: +61 7 3365 4417)
                AusCERT personnel answer during Queensland business 
                hours which are GMT+10:00 (AEST).  On call after hours 
                for member emergencies only.

-----BEGIN PGP SIGNATURE-----
Version: 2.6.3i
Charset: noconv
Comment: http://www.auscert.org.au/render.html?it=1967

iQCVAwUBPnhFfyh9+71yA2DNAQE9TgP/VmLNVWHFWPFgRfmxnnvh0YeJkLoz2H0f
4zjdCmBAeUvyjD+7aAYGI4FnZLiCwXl0BHc0KAr9jdbfMC32QrxtOtFe5KGB4wtc
TSTuUC8GkR13GoNeL0Jf02QuTGJLkCWAdhq4S7DybVhR1N46YXLv5K3LZ5054NgT
13sGQ0ZxxfI=
=6LXY
-----END PGP SIGNATURE-----