Cummulative update

Question

Hi All

I am using exchange 2016 hybrid environment. i have 4 servers in DAG.
i am using the below exchange 2016 version

Name : server01
Edition : Coexistence
AdminDisplayVersion : Version 15.1 (Build 2176.2)

i have the below vulnerabilities deleted on my server

CVE-2021-34473
CVE-2021-34523
CVE-2021-31207

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34473
will Microsoft Exchange Server 2016 Cumulative Update 21 fix this issue. can i go head and install CU21 directly or i need to go with other version and update to this. Does this update require schema update.

https://www.microsoft.com/en-us/download/details.aspx?id=103242

Answer 1

Hi @Glenn Maxwell ,

You server should be CU19 based on the Build number 15.1.2176.2.

Then you need to first install the CU21 full installation patch and then install the July SU patch. And yes you need to run commands like /prepareSchema if you are going to install in unattended mode. In addition, you should put your servers in maintance mode because of the DAG.

Kindly suggest that you could check for this article and see what you need to do: https://assistants.microsoft.com/assistants/#/session/bb2ef9b8-cb02-4fb1-9558-a5a2932af5c5

After installed all CU and SU patches on your servers, then exit from maintance mode and see if the upgrade was successfully installed.
July SU: https://techcommunity.microsoft.com/t5/exchange-team-blog/released-july-2021-exchange-server-security-updates/ba-p/2523421

Best regards,
Lou

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