[Full-disclosure] Microsoft MSDTC NdrAllocate Validation Vulnerability

McAfee, Inc.
McAfee Avert(tm) Labs Security Advisory
Public Release Date: 2006-05-09

Microsoft MSDTC NdrAllocate Validation Vulnerability

CVE-2006-0034

•   Synopsis
  

There is an RPC procedure within the MSDTC interface in msdtcprx.dll
that may be called remotely without user credentials in such a way that
triggers a denial-of-service in the Distributed Transaction Coordinator
(MSDTC) service.

Exploitation can at most lead to a denial of service and therefore the
risk factor is at medium.

•   Vulnerable Systems
  

Microsoft Windows 2000
Microsoft Windows XP
Microsoft Windows Server 2003

•   Vulnerability Information
  

The msdtcprx.dll shared library contains RPC procedures for use with
the Distributed Transaction Coordinator (MSDTC) service utilized in
Microsoft Windows.

By sending a large (greater than 4k) request to BuildContextW(), a
size check can be bypassed and a bug in NdrAllocate() may be reached.

This vulnerability was reported to Microsoft on October 12, 2005

•   Resolution
  

Microsoft has provided a patch for this issue. Please see their
bulletin, KB913580, for more information on obtaining and installing
the patch.

•   Credits
  

This vulnerability was discovered by Chen Xiaobo of McAfee Avert Labs.

•   Legal Notice
  

Copyright (C) 2006 McAfee, Inc.
The information contained within this advisory is provided for the
convenience of McAfee's customers, and may be redistributed provided
that no fee is charged for distribution and that the advisory is not
modified in any way. McAfee makes no representations or warranties
regarding the accuracy of the information referenced in this document,
or the suitability of that information for your purposes.

McAfee, Inc. and McAfee Avert Labs are registered Trademarks of McAfee,
Inc. and/or its affiliated companies in the United States and/or other
Countries. All other registered and unregistered trademarks in this
document are the sole property of their respective owners.

Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/