__________________________________________________________

                       The U.S. Department of Energy
                   Computer Incident Advisory Capability
                           ___  __ __    _     ___
                          /       |     /_\   /
                          \___  __|__  /   \  \___
             __________________________________________________________

                             INFORMATION BULLETIN

   Unchecked Buffer in Microsoft Windows Shell Could Enable System Compromise
                     [Microsoft Security Bulletin MS03-027]

July 17, 2003 21:00 GMT                                           Number N-120
______________________________________________________________________________
PROBLEM:       An unchecked buffer exists in one of the functions used by the 
               Windows shell to extract custom attribute information from 
               certain folders. A security vulnerability results because it is 
               possible for a malicious user to construct an attack that could 
               exploit this flaw and execute code on a user’s system. 
PLATFORM:      Microsoft Windows XP 
DAMAGE:        A successful attack could have the effect of either causing the 
               Windows shell to fail, or causing an attacker’s code to run on 
               the user’s computer in the security context of the user. 
SOLUTION:      Apply patch as stated in Microsoft's security bulletin. 
______________________________________________________________________________
VULNERABILITY  The risk is MEDIUM. In order to exploit this vulnerability, an 
ASSESSMENT:    attacker needs to create a Desktop.ini file that contains 
               corrupt attributes and host it on a network or Internet share. 
               The attacker could then attempt to lure users to that share. 
______________________________________________________________________________
LINKS: 
 CIAC BULLETIN:      http://www.ciac.org/ciac/bulletins/n-120.shtml 
 ORIGINAL BULLETIN:                                                           
                     http://www.microsoft.com/technet/treeview/
                      default.asp?url=/technet/security/bulletin/MS03-027.asp 
 PATCHES:                                                                     
                     http://microsoft.com/downloads/
                      details.aspx?FamilyId=27D02AF5-A2E1-4E25-9D16-502886161A35
                       &displaylang=en 
                     http://microsoft.com/downloads/
                      details.aspx?FamilyId=4BA84E2B-49F9-4416-8745-51F03503AB7D
                       &displaylang=en 
______________________________________________________________________________

[***** Start Microsoft Security Bulletin MS03-027 *****]

Microsoft Security Bulletin MS03-027 

Unchecked Buffer in Windows Shell Could Enable System 
Compromise (821557)
Originally posted: July 16, 2003

Updated: July 17, 2003

Summary
Who should read this bulletin: Customers using Microsoft® Windows® XP 

Impact of vulnerability: Run code of an attacker's choice 

Maximum Severity Rating: Important 

Recommendation: Customers should install the patch at the earliest 
opportunity. 

End User Bulletin: An end-user version of this bulletin is available at: 
http://www.microsoft.com/security/security_bulletins/ms03-027.asp 

Affected Software: Affected Software: 

* Microsoft Windows XP 

Not affected Software: 

* Microsoft Windows Millennium Edition 
* Microsoft Windows NT® Server 4.0 
* Microsoft Windows NT® 4.0, Terminal Server Edition 
* Microsoft Windows 2000 
* Microsoft Windows Server 2003 

Technical details 

Technical description: 

The Windows shell is responsible for providing the basic framework of the Windows 
user interface experience. It is most familiar to users as the Windows desktop. 
It also provides a variety of other functions to help define the user's computing 
session, including organizing files and folders, and providing the means to start 
programs. 

An unchecked buffer exists in one of the functions used by the Windows shell to 
extract custom attribute information from certain folders. A security vulnerability 
results because it is possible for a malicious user to construct an attack that 
could exploit this flaw and execute code on the user’s system. 

An attacker could seek to exploit this vulnerability by creating a Desktop.ini file 
that contains a corrupt custom attribute, and then host it on a network share. If a 
user were to browse the shared folder where the file was stored, the vulnerability 
could then be exploited. A successful attack could have the effect of either 
causing the Windows shell to fail, or causing an attacker’s code to run on the 
user’s computer in the security context of the user. 

Mitigating factors: 

* In the case where an attacker’s code was executed, the code would run in the 
  security context of the user. As a result, any limitations on the user's ability 
  would also restrict the actions that an attacker's code could take. 
* An attacker could only seek to exploit this vulnerability by hosting a malicious 
  file on a share. 
* This vulnerability only affects Windows XP Service Pack 1. Users running Windows 
  XP Gold are not affected. 

Severity Rating: 	Windows XP 	Important 

The above assessment is based on the types of systems affected by the vulnerability, 
their typical deployment patterns, and the effect that exploiting the vulnerability 
would have on them. 

Vulnerability identifier: CAN-2003-0306 

Tested Versions:
Microsoft tested Windows Millennium, Windows NT Server 4.0, Windows NT 4.0 Terminal 
Server Edition, Windows 2000, Windows XP, and Windows Server 2003 to assess whether 
they are affected by this vulnerability. Previous versions are no longer supported, 
and may or may not be affected by this vulnerability. 

Patch availability

Download locations for this patch 

* Microsoft Windows XP 32 bit Edition 
* Microsoft Windows XP 64 bit Edition 

Additional information about this patch 

Installation platforms: 
This patch can be installed on systems running Windows XP Service Pack 1. 

Inclusion in future service packs:
The fix for this issue will be included Windows XP Service Pack 2. 

Reboot needed: Yes 

Patch can be uninstalled: Yes 

Superseded patches: None. 

Verifying patch installation: 

* To verify that the patch has been installed on the machine, confirm that the 
  following registry key has been created on the machine: 
  HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows XP\SP2\KB821557 

* To verify the individual files, use the date/time and version information 
  provided in the following registry key:
  HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows XP\SP2\KB821557\Filelist 

Caveats:
None 

Localization:
Localized versions of this patch are available at the locations discussed in 
"Patch Availability". 

Obtaining other security patches: 
Patches for other security issues are available from the following locations: 

* Security patches are available from the Microsoft Download Center, and can be 
  most easily found by doing a keyword search for "security_patch". 
* Patches for consumer platforms are available from the WindowsUpdate site 

Other information: 
Support: 

* Microsoft Knowledge Base article 821557 discusses this issue and will be available 
  approximately 24 hours after the release of this bulletin. Knowledge Base articles 
  can be found on the Microsoft Online Support site. 
* Technical support is available from Microsoft Product Support Services. There is no 
  charge for support calls associated with security patches. 

Security Resources: The Microsoft TechNet Security Web Site provides additional 
information about security in Microsoft products. 

Disclaimer: 
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. 

Revisions: 

* V1.0 (July 16, 2003): Bulletin published. 
* V1.1 (July 17, 2003): Corrected CVE Candidate number, added Windows XP Gold 
  information to the Frequently Asked Questions section. 

[***** End Microsoft Security Bulletin MS03-027 *****]

_______________________________________________________________________________

CIAC wishes to acknowledge the contributions of Microsoft Corporation for the 
information contained in this bulletin.
_______________________________________________________________________________


CIAC, the Computer Incident Advisory Capability, is the computer
security incident response team for the U.S. Department of Energy
(DOE) and the emergency backup response team for the National
Institutes of Health (NIH). CIAC is located at the Lawrence Livermore
National Laboratory in Livermore, California. CIAC is also a founding
member of FIRST, the Forum of Incident Response and Security Teams, a
global organization established to foster cooperation and coordination
among computer security teams worldwide.

CIAC services are available to DOE, DOE contractors, and the NIH. CIAC
can be contacted at:
    Voice:    +1 925-422-8193 (7x24)
    FAX:      +1 925-423-8002
    STU-III:  +1 925-423-2604
    E-mail:   ciac@ciac.org

Previous CIAC notices, anti-virus software, and other information are
available from the CIAC Computer Security Archive.

   World Wide Web:      http://www.ciac.org/
   Anonymous FTP:       ftp.ciac.org

PLEASE NOTE: Many users outside of the DOE, ESnet, and NIH computing
communities receive CIAC bulletins.  If you are not part of these
communities, please contact your agency's response team to report
incidents. Your agency's team will coordinate with CIAC. The Forum of
Incident Response and Security Teams (FIRST) is a world-wide
organization. A list of FIRST member organizations and their
constituencies can be obtained via WWW at http://www.first.org/.

This document was prepared as an account of work sponsored by an
agency of the United States Government. Neither the United States
Government nor the University of California nor any of their
employees, makes any warranty, express or implied, or assumes any
legal liability or responsibility for the accuracy, completeness, or
usefulness of any information, apparatus, product, or process
disclosed, or represents that its use would not infringe privately
owned rights. Reference herein to any specific commercial products,
process, or service by trade name, trademark, manufacturer, or
otherwise, does not necessarily constitute or imply its endorsement,
recommendation or favoring by the United States Government or the
University of California. The views and opinions of authors expressed
herein do not necessarily state or reflect those of the United States
Government or the University of California, and shall not be used for
advertising or product endorsement purposes.

LAST 10 CIAC BULLETINS ISSUED (Previous bulletins available from CIAC)

N-110: Red Hat Updated XFree86 Packages Provide Security and Bug Fixes
N-111: Red Hat Updated unzip Packages Fix Trojan Vulnerability
N-112: Red Hat Updated PHP Packages Fix Bugs
N-113: Sun Buffer Overflow in LDAP Name Service
N-114: Buffer Overrun in Microsoft HTML Converter Could Allow Code Execution
N-115: Buffer Overrun in Microsoft Windows Could Lead to Data Corruption
N-116: Flaw in Microsoft Windows Message Handling through Utility Manager Could Enable Privilege Elevation
N-117: Microsoft RPC Interface Buffer Overrun Vulnerability
N-118: Cisco IOS Interface Blocked by IPv4 Packet
N-119: Microsoft Internet Security and Acceleration (ISA) Server Error Pages Could Allow Cross-Site Scripting Attack