Exchange Security Update – Oct. 2021

Microsoft has released another Exchange Security Update (October 2021), which addresses vulnerbilities found in:

• Exchange 2013
• Exchange 2016
• Exchange 2019

The Security Update is available for the specific Cumulative Update level (CU) your Exchange is running, if you are not up-to-date, to the latest CU, you might have to update the CU before applying the Security Update.

The update path is the following:

If you only have an Exchange Hybrid running, you will still need to update your Exchange environment.

See the original blog post for more info and this, as well use the new Exchange Update Wizard, if in doubt about the upgrade process:

• https://aka.ms/ExchangeUpdateWizard 

If you manually install the Updates, they can be downloaded here:

• Exchange Server 2013 CU23
• Exchange Server 2016 CU21 and CU22
• Exchange Server 2019 CU10 and CU11

Remember to install them from an elevated command prompt.

Reference – the original blog post:

• https://techcommunity.microsoft.com/t5/exchange-team-blog/released-october-2021-exchange-server-security-updates/ba-p/2838287?WT.mc_id=M365-MVP-5000284

/Happy Patching! 🙂