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Released: November 2021 Exchange Server Security Updates

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The_Exchange_Team
Platinum Contributor
Nov 09, 2021
Microsoft has released security updates for vulnerabilities found in: Exchange Server 2013 Exchange Server 2016 Exchange Server 2019 These updates are available for the following specific...
Updated Jan 12, 2022
Version 17.0
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Exchange 2013
exchange 2016
exchange 2019
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LukasSMSFT's avatar
LukasSMSFT
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Nov 11, 2021

dchan268 Thanks, will report it to the responsible team.

 

There is a Schema change with CU21 (see: https://docs.microsoft.com/en-us/exchange/plan-and-deploy/active-directory/ad-schema-changes?view=exchserver-2016#exchange-2016-cu21-active-directory-schema-changes) so you need proper permission to perform this change (it'll be performed even if you go straight to CU22). 

 

There are also new prerequisites (IIS URL Rewrite Module and [on Server 2012 only - Update for Universal C Runtime in Windows (KB2999226)]) which are required for the newly introduced Exchange Emergency Mitigation Service. 

See: https://docs.microsoft.com/en-us/Exchange/plan-and-deploy/prerequisites?view=exchserver-2016#exchange-2016-mailbox-servers-on-windows-server-2016 

 

Please find our update best practices here: https://docs.microsoft.com/en-us/exchange/plan-and-deploy/install-cumulative-updates?view=exchserver-2016