Vulnerability Note VU#319331

Microsoft Windows DNS Server response validation vulnerability

Overview

The Microsoft Windows DNS server contains a response validation vulnerability. If successfully exploited, this vulnerability may allow an attacker to poison the affected DNS server's cache.

I. Description

The Domain Name System (DNS) is responsible for translating host names to IP addresses (and vice versa) and is critical for the normal operation of internet-connected systems.

Per Microsoft Security Bulletin MS09-008:

A response validation vulnerability exists in Windows DNS Server. The vulnerability could allow an unauthenticated remote attacker to send specially crafted queries to a DNS server so as to allow greater predictability of transaction IDs used by the DNS server and thus to redirect Internet traffic from legitimate locations.

II. Impact

An attacker may be able to insert arbitrary values in the DNS cache. An attacker with the ability to conduct a successful attack can cause a nameserver's clients to contact the incorrect, and possibly malicious, hosts for particular services. Consequently, web traffic, email, and other important network data can be redirected to systems under the attacker's control.

III. Solution

Upgrade

Microsoft has released an update to address this issue. See http://www.microsoft.com/technet/security/bulletin/MS09-008.mspx for more information.

Systems Affected

Vendor	Status	Date Updated
Microsoft Corporation	Vulnerable		2009-03-10

References

http://www.microsoft.com/technet/security/Bulletin/MS09-mar.mspx
http://www.microsoft.com/technet/security/bulletin/MS09-008.mspx

Credit

Information from Microsoft Security Bulletin MS09-008 was used in this report. Microsoft credits Kevin Day and Dave Dagon for providing assistance with this issue.

This document was written by Ryan Giobbi.

Other Information

Date Public	03/10/2009
Date First Published	03/10/2009 01:34:49 PM
Date Last Updated	03/17/2009
CERT Advisory
CVE Name	CVE-2009-0234
Metric	10.13
Document Revision	21

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