sa2003-01.txt

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NSFOCUS Security Advisory(SA2003-01)  
  
Topic: Microsoft Windows XP Redirector Local Buffer Overflow Vulnerability  
  
Release Date: 2003-3-27  
  
CVE CAN ID: CAN-2003-0004  
  
Affected system:  
===================  
  
- - Microsoft Windows XP  
- - Microsoft Windows XP SP1  
  
Summary:  
=========  
  
NSFOCUS Security Team has found a buffer overflow vulnerability in Microsoft  
Windows XP Redirector. Exploiting the vulnerability local attackers  
could crash the system or gain local system privilege by carefully crafted  
code.  
  
Description:  
============  
  
The Windows Redirector is used to access files, whether local or remote.It  
is used to access network shares by net use command.  
  
A security vulnerability exists in the Windows Redirector on Windows XP.An  
unchecked length in handling the received parameter information causes a  
buffer overflow vulnerability. Exploiting the vulnerability a non-privileged  
user could cause system blue screen and reboot. If the code was carefully  
crafted, attackers could execute arbitrary command in system privilege. At  
present no remote exploitation method has been found.  
  
Only Windows XP is vulnerable to the issue. Windows NT 4.0, Windows NT 4.0  
Terminal Server Edition, and Windows 2000 do not contain the vulnerable code  
and are not affected by this vulnerability.  
  
Exploit:  
==========  
  
Enter the following command as a non-privileged user in the command line  
window:  
  
c:\> net use \\AAAA...AAA[about 1000-2000 'A' characters]\A  
  
Windows XP will become blue screen or reboot immediately.  
  
Note: Attackers have to be able to login interactively.  
  
Workaround:  
=============  
  
Prohibit untrusted user login to your system.  
  
Vendor Status:  
==============  
  
Microsoft has issued a Security Bulletin(MS03-005) and the related patch.  
  
Detailed Microsoft Security Bulletin is available at:  
  
http://www.microsoft.com/technet/security/bulletin/ms03-005.asp  
  
Patches are available at:  
  
. Microsoft Windows XP 32-bit Edition:  
http://microsoft.com/downloads/details.aspx?FamilyId=33DABD1F-505E-48ED-B9BD-CDAC0F8A2BC1  
  
. Microsoft Windows XP 64-bit Edition:  
http://microsoft.com/downloads/details.aspx?FamilyId=A2258F4E-9A69-4537-9469-0DDEB4BB76F8  
  
Additional Information:  
========================  
  
The Common Vulnerabilities and Exposures (CVE) project has assigned the  
name CAN-2003-0004 to this issue. This is a candidate for inclusion in the  
CVE list (http://cve.mitre.org), which standardizes names for security  
problems. Candidates may change significantly before they become official  
CVE entries.  
  
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==========  
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Copyright 1999-2003 NSFOCUS. All Rights Reserved. Terms of use.  
  
  
NSFOCUS Security Team <[email protected]>  
NSFOCUS INFORMATION TECHNOLOGY CO.,LTD  
(http://www.nsfocus.com)  
  
PGP Key: http://www.nsfocus.com/homepage/research/pgpkey.asc  
Key fingerprint = F8F2 F5D1 EF74 E08C 02FE 1B90 D7BF 7877 C6A6 F6DA  
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