Vulnerability Note VU#399260

Microsoft SQL Server 2000 contains heap buffer overflow in SQL Server Resolution Service

Original Release date: 26 Jul 2002 | Last revised: 05 Feb 2003


Microsoft SQL Server 2000 contains a remotely exploitable heap buffer overflow that allows attackers to execute arbitrary code with the same privileges as the SQL server.


The SQL Server Resolution Service (SSRS) was introduced in Microsoft SQL Server 2000 to provide referral services for multiple server instances running on the same machine. The service listens for requests on UDP port 1434 and returns the IP address and port number of the SQL server instance that provides access to the requested database.

The SSRS contains a heap buffer overflow that allows an attacker to execute arbitrary code by sending a crafted request to port 1434/udp. The code within such a request will be executed by the server host with the privileges of the SQL Server service account.


This vulnerability allows unauthenticated remote attackers to execute arbitrary code with the privileges of the SQL service account. If the privileges of the service account are elevated via VU#796313, this vulnerability may result in compromise of the server host.


Apply a patch

This vulnerability was originally addressed by Microsoft in Security Bulletin MS02-039. In January 2003, Microsoft updated MS02-039 to recommend that customers apply the patch from Microsoft Security Bulletin MS02-061, which addresses additional vulnerabilities. For more information, please see

    This vulnerability also affects any products that include the Microsoft Desktop Engine (MSDE) 2000. For more information, please see

    Block port 1434/udp

    As a workaround, system administrators can use a firewall to block port 1434/udp at an appropriate network border, thus preventing external attackers from exploiting this vulnerability.

    Systems Affected (Learn More)

    VendorStatusDate NotifiedDate Updated
    Cisco Systems Inc.Affected26 Jan 200327 Jan 2003
    Microsoft CorporationAffected25 Jul 200225 Jul 2002
    If you are a vendor and your product is affected, let us know.

    CVSS Metrics (Learn More)

    Group Score Vector
    Base N/A N/A
    Temporal N/A N/A
    Environmental N/A N/A



    The CERT/CC thanks Microsoft for the information provided in their advisory and NGSSoftware for their discovery and analysis of this vulnerability.

    This document was written by Jeffrey P. Lanza.

    Other Information

    • CVE IDs: CAN-2002-0649
    • CERT Advisory: CA-2002-22
    • Date Public: 24 Jul 2002
    • Date First Published: 26 Jul 2002
    • Date Last Updated: 05 Feb 2003
    • Severity Metric: 43.28
    • Document Revision: 43


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