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MS03-033: Security Update for Microsoft Data Access Components

View products that this article applies to.


Microsoft Data Access Components (MDAC) is a collection of components that is used to provide database connectivity on Microsoft Windows operating systems. MDAC is a ubiquitous technology, and it is likely to be present on most Windows systems.

By default, MDAC is included as part of Microsoft Windows XP, Microsoft Windows 2000, and Microsoft Windows Millennium Edition (Me). A number of other products and technologies also include or install MDAC. For example, the Microsoft Windows NT 4.0 Option Pack and Microsoft SQL Server 2000 both include MDAC, and some MDAC components are present as part of Microsoft Internet Explorer even if MDAC itself is not installed. MDAC is also available as a stand-alone technology. To download MDAC, visit the following Microsoft Web site: Versions of MDAC earlier than 2.8 contain a flaw that results in a buffer overflow vulnerability. MDAC provides the underlying functionality for a number of database operations, such as connecting to remote databases and returning data to a client. When a client computer on a network tries to see a list of computers that are running Microsoft SQL Server and that are residing on the network, it sends a broadcast request to all the devices that are on the network. Because of a flaw in a specific MDAC component, an attacker can respond with a specially crafted packet that causes a buffer overflow to occur. The security patch that is described in this article resolves the buffer overflow vulnerability.

An attacker who successfully exploits this flaw can gain the same level of user rights over the system as the application that initiated the aforementioned broadcast request. This can include creating, modifying, or deleting data on the system; reconfiguring the system; reformatting the hard disk; or running programs of the attacker�s choice on the system.

The mitigating factors are as follows:
  • For an attack to be successful, an attacker must simulate a computer that is running Microsoft SQL Server on the same subnet as the target system.
  • Code that is executed on the client system would only run under the administrative credentials of the logged-on user.
  • MDAC version 2.8 does not contain the flaw that this bulletin fixes. For additional information about MDAC 2.8, click the following article number to view the article in the Microsoft Knowledge Base:
    820761� List of significant fixes that are included in MDAC 2.8

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More information

Download Information

The following file is available for download from the Microsoft Download Center:
Download the Microsoft Data Access Components (MDAC) Security Patch MS03-033 package now. Release Date: 20 August 2003

For additional information about how to download Microsoft Support files, click the following article number to view the article in the Microsoft Knowledge Base:
119591� How to Obtain Microsoft Support Files from Online Services
Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help to prevent any unauthorized changes to the file.

Note This patch is not language-specific.


You must be running one of the following versions of MDAC:
  • MDAC 2.5 Service Pack 2
  • MDAC 2.5 Service Pack 3
  • MDAC 2.6 Service Pack 2
  • MDAC 2.7 RTM
  • MDAC 2.7 Service Pack 1
Older versions of MDAC are vulnerable but are not supported. You must upgrade to an MDAC version that is listed to apply this patch.

You can determine the version of MDAC you are running by checking the registry. The version information is found in the following key:

To check the registry, follow these steps:
  1. Click Start, and then click Run.
  2. In the Open text box, type regedit, and then click OK. This starts Registry Editor.
  3. In the navigation pane, locate the following key:
  4. In the details pane, locate FullInstallVer and Version inthe Name column. Each of these keys has corresponding version information in the Data column. Compare this information with the version information in the following table.
  5. When you are finished, click Exit on the Registry menu to close Registry Editor.
Collapse this tableExpand this table
MDAC VersionFullInstallVer
MDAC 2.5 RTM2.50.xxxx.x
MDAC 2.5 SP1 2.51.xxxx.x
MDAC 2.5 SP2 2.52.xxxx.x
MDAC 2.5 SP32.53.xxxx.x
MDAC 2.6 RTM 2.60.xxxx.x
MDAC 2.6 SP1 2.61.xxxx.x
MDAC 2.6 SP22.62.xxxx.x
MDAC 2.7 RTM2.70.xxxx.x
MDAC 2.7 SP12.71.xxxx.x
MDAC 2.8 RTM 2.80.xxxx.x
For additional information about how to determine your version of MDAC, click the following article number to view the article in the Microsoft Knowledge Base:
301202� How to check for MDAC version

Installation information

This security patch is installed through an installer program.

Note The installer program is in English only.

Installation options

This update supports the following Setup switches:
Switch            Description
/?                Displays the list of installation switches
/Q                Quiet mode
/T:<full path>    Specifies the temporary working folder
/C                Extract files only to the folder when it is used with /T
/C:<Cmd>          Override Install Command that author defines
/N                No restart dialog box

For example, the following command-line command installs the update without any user intervention and suppresses a restart:

Q823718_MDAC_SecurityPatch /C:"dahotfix.exe /q /n" /q

The /q switch that is specified for dahotfix.exe is for a silent install, and the /n switch suppresses the restart.

Warning Your computer is vulnerable until you restart it.

Restart requirement

You must restart your computer after you apply this update.

Removal information

This security patch cannot be removed after it has been installed.

Security patch replacement information

This security patch replaces the security patch that is provided in Microsoft Security Bulletin MS02-040. For more information about Microsoft Security Bulletin MS02-040, visit the following Microsoft Web site: For additional information about Microsoft Security Bulletin MS02-040, click the following article number to view the article in the Microsoft Knowledge Base:
326573� MS02-040: Unchecked buffer in OpenRowset updates

File Information

The English version of this security patch has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.

MDAC 2.5 Service Pack 2

   	Date         Time   Version            Size    File name
   23-Jul-2003  20:56  3.520.6100.40     212,992  Odbc32.dll       
   21-Jul-2003  22:24         24,848  Odbcbcp.dll      
   23-Jul-2003  02:29  3.520.6100.40     102,672  Odbccp32.dll     
   21-Jul-2003  22:24        524,560  Sqlsrv32.dll     

MDAC 2.5 Service Pack 3

   	Date         Time   Version            Size    File name
   24-Jul-2003  00:13  3.520.6300.40     212,992  Odbc32.dll       
   21-Jul-2003  22:24         24,848  Odbcbcp.dll      
   24-Jul-2003  00:11  3.520.6300.40     102,672  Odbccp32.dll     
   21-Jul-2003  22:24        524,560  Sqlsrv32.dll     

MDAC 2.6 Service Pack 2

   	Date         Time   Version            Size    File name
   21-Jul-2003  17:28  2000.80.746.0      86,588  Dbnetlib.dll     
   22-Jul-2003  22:04  3.520.7501.40     217,360  Odbc32.dll       
   21-Jul-2003  17:28  2000.80.746.0      29,252  Odbcbcp.dll      
   22-Jul-2003  22:04  3.520.7501.40     102,672  Odbccp32.dll     
   31-Jul-2003  23:07  2000.80.746.0     479,800  Sqloledb.dll     
   21-Jul-2003  17:28  2000.80.746.0     455,236  Sqlsrv32.dll     


   	Date         Time   Version            Size    File name
   31-Jul-2003  17:49  2000.81.9001.40    61,440  Dbnetlib.dll     
   22-Jul-2003  23:04  3.520.9001.40     204,800  Odbc32.dll       
   22-Jul-2003  23:10  2000.81.9001.40    24,576  Odbcbcp.dll      
   22-Jul-2003  23:10  3.520.9001.40      94,208  Odbccp32.dll     
   31-Jul-2003  17:49  2000.81.9001.40   450,560  Sqloledb.dll     
   22-Jul-2003  23:08  2000.81.9001.40   356,352  Sqlsrv32.dll     

MDAC 2.7 Service Pack 1

   	Date         Time   Version            Size    File name
   22-Jul-2003  18:27  2000.81.9041.40    61,440  Dbnetlib.dll     
   22-Jul-2003  18:22  3.520.9041.40     204,800  Odbc32.dll       
   22-Jul-2003  18:28  2000.81.9041.40    24,576  Odbcbcp.dll      
   22-Jul-2003  18:28  3.520.9041.40      98,304  Odbccp32.dll     
   31-Jul-2003  18:47  2000.81.9041.40   471,040  Sqloledb.dll     
   22-Jul-2003  18:27  2000.81.9041.40   385,024  Sqlsrv32.dll     


Make sure that you have the correct versions of the files that are listed in this article.

You can also verify the patch installation by checking for the existence of the following entries under the
key and installed file versions. You should see the following entry:

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For additional information about this security patch, see Microsoft Security Bulletin MS03-033:

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Keywords: KB823718, kbfix, kbbug, kbsecbulletin, kbsecurity, kbsecvulnerability

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Article Info
Article ID : 823718
Revision : 8
Created on : 5/21/2007
Published on : 5/21/2007
Exists online : False
Views : 178