Microsoft KB5004238 Information

Lexmark Updated Drivers to fix Authentication after Microsoft July 13, 2021 Server Patches are applied.

CAC Modernization Image

On July 13th Microsoft released a service patch that addressed CVE-2021-33764 among other things. This patch made inoperative CAC and PIV smart card authentication on printer and multifunction devices of all manufactures, including Lexmark. This is detailed in Microsoft Knowledge Net Article KB5005408. Lexmark is the first manufacturer to provide a fix for this issue. The details are below.
Microsoft has created a temporary mitigation for this issue which the majority of the Department of Defense and federal agencies have adopted. This mitigation is set to be reversed in January of 2022. If your Lexmark MFP is relying on this mitigation, it is important that you apply the fixes below before the January 2022 date.

Actions/Changes to CAC/PIV-enabled Multi-Function Devices (MFDs) which must be performed:

  • Where the model number has two leading alpha character (CX### / MX###).
  • C748, C792, C925, C950, X548, X746, X748, X792, X925, X950, X952, and X954.
  • Models that do not fit the description above are not currently planned too to be updated.
    • Please contact your Lexmark Account Manager to replace the older devices or complete and submit the Request Information form section on this page for someone to contact you. These older models should work with the mitigation detailed in KB5005408. However, they will not work once the mitigation is reversed in January 2022.

User impact if the above actions/changes to CAC/PIV-enabled MFDs are not performed:

  • Smartcard Authentication on MFDs will fail come February 2022.

For additional instructions and to receive the necessary software to prepare my Lexmark multifunction device, please fill in the Request Information form section on this page.

CAC Modernization Request Information

To access detailed instructions and the required MFD update files or if you would like to have your Lexmark Account Manager contact you, please complete and submit this form.

Need other technical assistance with your CAC Modernization efforts please contact our Technical Support Center at:

For DOD CONUS Support  1-800-Lexmark (539-6275) Option 1, Option 2, Option 2. 

For DOD OCONUS SUPPORT to open new cases or ask for updates.


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The additional instructions and the necessary software needed to prepare your Lexmark multifunction devices are provided via this link – CAC Modernization Instructions.


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