Vulnerability Note VU#827267

Microsoft Server service RPC stack buffer overflow vulnerability

Overview

A stack buffer overflow vulnerability in the Microsoft Windows Server service may allow a remote, unauthenticated attacker to execute arbitrary code with SYSTEM privileges.

I. Description

MS08-067 includes the following information about the Microsoft Server service:

The Server service provides RPC support, file print support and named pipe sharing over the network. The Server service allows the sharing of your local resources (such as disks and printers) so that other users on the network can access them. It also allows named pipe communication between applications running on other computers and your computer, which is used for RPC.

The Microsoft Server service contains a stack buffer overflow vulnerability in the handling of Remote Procedure Call (RPC) messages.

Exploit code for this vulnerability is publicly available, and the vulnerability is being currently exploited in the wild.

II. Impact

A remote, unauthenticated attacker may be able to execute arbitrary code with SYSTEM privileges on a vulnerable system.

Certain versions of malicious code called Conficker or Downadup attempt to exploit this vulnerability.

III. Solution

Apply the updates referenced in Microsoft Security Bulletin MS08-067.

Block or Restrict Access

Block access to SMB services (139/tcp, 445/tcp) from untrusted networks such as the Internet. This and additional workarounds are provide in Microsoft Security Bulletin MS08-067.

Systems Affected

Vendor	Status	Date Updated
Microsoft Corporation	Vulnerable		2008-11-05

References

http://www.microsoft.com/technet/security/Bulletin/ms08-067.mspx
http://blogs.technet.com/swi/archive/2008/10/23/More-detail-about-MS08-067.aspx
http://www.microsoft.com/technet/security/bulletin/ms08-oct.mspx
http://blogs.msdn.com/sdl/archive/2008/10/22/ms08-067.aspx
https://www.securecoding.cert.org/confluence/display/seccode/FIO02-C.+Canonicalize+path+names+originating+from+untrusted+sources
https://www.securecoding.cert.org/confluence/display/seccode/STR31-C.+Guarantee+that+storage+for+strings+has+sufficient+space+for+character+data+and+the+null+terminator

Credit

Thanks to Microsoft for reporting this vulnerability.

This document was written by Will Dormann.

Other Information

Date Public	10/23/2008
Date First Published	10/23/2008 01:08:42 PM
Date Last Updated	11/02/2009
CERT Advisory
CVE Name	CVE-2008-4250
Metric	88.20
Document Revision	30

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