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Microsoft Windows DNS Server response validation vulnerability

Vulnerability Note VU#319331

Original Release Date: 2009-03-10 | Last Revised: 2009-03-17


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.


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.


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.



Microsoft has released an update to address this issue. See for more information.

Vendor Information


Microsoft Corporation Affected

Updated:  March 10, 2009



Vendor Statement

We have not received a statement from the vendor.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.


See for more information.

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CVSS Metrics

Group Score Vector
Base 0 AV:--/AC:--/Au:--/C:--/I:--/A:--
Temporal 0 E:Not Defined (ND)/RL:Not Defined (ND)/RC:Not Defined (ND)
Environmental 0 CDP:Not Defined (ND)/TD:Not Defined (ND)/CR:Not Defined (ND)/IR:Not Defined (ND)/AR:Not Defined (ND)



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

CVE IDs: CVE-2009-0234
Severity Metric: 10.13
Date Public: 2009-03-10
Date First Published: 2009-03-10
Date Last Updated: 2009-03-17 16:02 UTC
Document Revision: 21

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