[NT] Microsoft Distributed Transaction Controller Packet Relay DoS (MS05-051)

The following security advisory is sent to the securiteam mailing list, and can be found at the SecuriTeam web site: http://www.securiteam.com
- - promotion

The SecuriTeam alerts list - Free, Accurate, Independent.

Get your security news from a reliable source.
http://www.securiteam.com/mailinglist.html

- - - - - - - - -

Microsoft Distributed Transaction Controller Packet Relay DoS (MS05-051)
------------------------------------------------------------------------

SUMMARY

The Distributed Transaction Controller provides a method for disparate
processes to complete atomic transactions. The Transaction Internet
Protocol (TIP) is one the ways that the DTC service can be accessed. This
service is part of a standard installation on Windows NT 4.0, Windows
2000, Windows XP and Windows 2003.

Remote exploitation of a denial of service vulnerability within various
versions of Microsoft Corp.'s Windows operating system allows attackers to
flood systems with connection attempts from legitimate MSDTC servers.

DETAILS

Vulnerable Systems:
* Microsoft Windows 2000 SP4

The vulnerability specifically exists because of the functionality in the
TIP protocol that allows a remote IP address and port number to be
specified for a connection. The attack can be performed by connecting to
the MSDTC server and providing an identifier that contains the IP address
and port number to flood. After a specific sequence of commands, the
attacker can force an error and cause the DTC service to connect to the
target IP and port. The DTC service will continue to make connections to
that host and port, one at a time, per stalled transaction.

If the target host and port provides anything other than a certain set of
response messages to the IDENTIFY request on the connection, the DTC
service will disconnect and then reconnect to the service. The attacker
can keep submitting new transactions to the DTC service, increasing the
total number of connections made to the target.

Analysis:
Successful exploitation of this vulnerability could allow an attacker to
proxy a denial of service attack through a MSDTC server that they do not
otherwise have access to. An attacker could easily scan public IP ranges
and find servers with TIP enabled and then force them to flood a target
with repeated connections attempts.

This attack can also be used to cause a DoS on the MSDTC server itself by
specifying a loopback address with port 445. This service should not be
exposed to public networks, thus mitigating the risk of this
vulnerability.

Vendor response:
The vendor security advisory and appropriate patches are available at:
<http://www.microsoft.com/technet/security/Bulletin/MS05-051.mspx>
http://www.microsoft.com/technet/security/Bulletin/MS05-051.mspx

CVE Information:
<http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2005-1980>
CAN-2005-1980

Disclosure Timeline:
03/23/2005 Initial vendor notification
03/23/2005 Initial vendor response
10/11/2005 Coordinated public disclosure

ADDITIONAL INFORMATION

The information has been provided by
<mailto:idlabs-advisories@lists.idefense.com> iDEFENSE Labs Security
Advisories.
The original article can be found at:
<http://www.idefense.com/application/poi/display?id=319&type=vulnerabilities> http://www.idefense.com/application/poi/display?id=319&type=vulnerabilities

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

This bulletin is sent to members of the SecuriTeam mailing list.
To unsubscribe from the list, send mail with an empty subject line and body to: list-unsubscribe@securiteam.com
In order to subscribe to the mailing list, simply forward this email to: list-subscribe@securiteam.com

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

DISCLAIMER:
The information in this bulletin is provided "AS IS" without warranty of any kind.
In no event shall we be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages.