Microsoft Malicious Software Removal Tool: Administrator Compromise -- Existing Account

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

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

                               ESB-2015.1868
        Vulnerability in Microsoft Malicious Software Removal Tool
                    Could Allow Elevation of Privilege
                               15 July 2015

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

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

Product:           Microsoft Malicious Software Removal Tool
Publisher:         Microsoft
Operating System:  Windows
Impact/Access:     Administrator Compromise -- Existing Account
Resolution:        Patch/Upgrade
CVE Names:         CVE-2015-2418  

Original Bulletin: 
   https://technet.microsoft.com/en-us/library/security/3074162

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

Microsoft Security Advisory 3074162

Vulnerability in Microsoft Malicious Software Removal Tool Could Allow 
Elevation of Privilege

Published: July 14, 2015

Version: 1.0

Executive Summary

Microsoft is releasing this security advisory to inform customers that an 
update to the Microsoft Malicious Software Removal Tool (MSRT) is available 
that addresses a security vulnerability that was reported to Microsoft. The 
vulnerability could allow elevation of privilege if an attacker logs on to a 
target system and places a specially crafted dynamic link library (.dll) file
in a local directory. An authenticated attacker who successfully exploited the
vulnerability could elevate privileges on a target system. An attacker could 
then install programs; view, change, or delete data; or create new accounts 
with full administrative rights.

Administrators of enterprise installations should follow their established 
internal processes to ensure that updates are approved in their update 
management software, and that clients consume the updates accordingly.

Typically, no action is required of enterprise administrators or end users to
install updates for the Microsoft Malicious Software Removal Tool, because the
built-in mechanism for the automatic detection and deployment of updates will
apply the update within 48 hours of release. The exact timeframe depends on 
the software used, Internet connection, and infrastructure configuration.

Affected Software

Microsoft Malicious Software Removal Tool [1]

[1] Applies only to May 2015 or earlier versions of the Microsoft Malicious 
Software Removal Tool.

MSRT Race Condition Vulnerability - CVE-2015-2418

An elevation of privilege vulnerability exists in the Microsoft Malicious 
Software Removal Tool (MSRT) when it fails to properly handle a race condition
involving a DLL-planting scenario. An authenticated attacker who successfully
exploited this vulnerability could elevate privileges on a target system. An 
attacker could then install programs; view, change, or delete data; or create
new accounts with full administrative rights.

To exploit the vulnerability, an attacker would have to log on to the target 
system and place a specially crafted dynamic link library (.dll) file in a 
local directory. An attacker would then have to wait for the user to run MSRT,
which would in turn run the attackers malicious code to effectively increase 
privileges on the target system. The update addresses the vulnerability by 
correcting how MSRT handles race conditions.

- --------------------------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.

NOTE: Third Party Rights
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 follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.

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

===========================================================================
Australian Computer Emergency Response Team
The University of Queensland
Brisbane
Qld 4072

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-----
Comment: http://www.auscert.org.au/render.html?it=1967
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=sRPt
-----END PGP SIGNATURE-----