Published:
23 August 2002
Protect yourself against future threats.
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AUSCERT External Security Bulletin Redistribution
ESB-2002.456 -- Microsoft Security Bulletin MS02-045
Unchecked Buffer in Network Share Provider Can Lead to Denial of Service
(Q326830)
23 August 2002
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AusCERT Security Bulletin Summary
---------------------------------
Product: Windows NT 4.0 Workstation
Windows NT 4.0 Server
Windows NT 4.0 Terminal Server
Windows 2000 Professional
Windows 2000 Server
Windows 2000 Advanced Server
Windows XP Professional
Vendor: Microsoft
Platform: i386
IA-64
Impact: Execute Arbitrary Code/Commands
Denial of Service
Access Required: Remote
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Title: Unchecked Buffer in Network Share Provider Can Lead to
Denial of Service (Q326830)
Date: 22 August 2002
Software: Microsoft Windows NT 4.0 Workstation
Microsoft Windows NT 4.0 Server
Microsoft Windows NT 4.0 Server, Terminal Sever Edition
Microsoft Windows 2000 Professional
Microsoft Windows 2000 Server
Microsoft Windows 2000 Advanced Server
Windows XP Professional
Impact: Denial of Service
Max Risk: Moderate
Bulletin: MS02-045
Microsoft encourages customers to review the Security Bulletin at:
http://www.microsoft.com/technet/security/bulletin/MS02-045.asp.
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Issue:
======
SMB (Server Message Block) is the protocol Microsoft uses to share
files, printers, serial ports, and also to communicate between
computers using named pipes and mail slots. In a networked
environment, servers make file systems and resources available to
clients. Clients make SMB requests for resources and servers make
SMB responses in what described as a client server, request-
response protocol.
By sending a specially crafted packet request, an attacker can mount
a denial of service attack on the target server machine and crash
the system. The attacker could use both a user account and anonymous
access to accomplish this. Though not confirmed, it may be possible
to execute arbitrary code.
Mitigating Factors:
====================
- - - An administrator can block this attack by turning off anonymous
access. However, this does not prevent legitimate users from
exploiting this vulnerability.
- - - An administrator can block access to SMB ports from untrusted
networks. By blocking TCP ports 445 and 139 at the network
perimeter, administrators can prevent this attack from untrusted
parties. In a file and printing environment, this may not be a
practical solution for legitimate users.
- - - An administrator can stop the Lanman server service which prevents
the attack, but again may not be suitable on a file and print
sharing server.
Risk Rating:
============
- Internet systems: Low
- Intranet systems: Moderate
- Client systems: Moderate
Patch Availability:
===================
- A patch is available to fix this vulnerability. Please read the
Security Bulletin at
http://www.microsoft.com/technet/security/bulletin/ms02-045.asp
for information on obtaining this patch.
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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.
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