Microsoft MSDTC NdrAllocate Validation Vulnerability
McAfee, Inc.
McAfee Avert? Labs Security Advisory
Public Release Date: 2006-05-09
Microsoft MSDTC NdrAllocate Validation Vulnerability
CVE-2006-0034
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? 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.
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? Vulnerable Systems
Microsoft Windows 2000
Microsoft Windows XP
Microsoft Windows Server 2003
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? 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
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? Resolution
Microsoft has provided a patch for this issue. Please see their
bulletin, KB913580, for more information on obtaining and installing
the patch.
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? Credits
This vulnerability was discovered by Chen Xiaobo of McAfee Avert Labs.
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? Legal Notice
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