Hafnium - Patch for Server 2013 only with installed CU 23 ?

Copper Contributor

Dear community


I try to figure out if the patch for Exchange 2013 only can be installed if you have CU23 already installed ( Screenshot).

Does someone know if this is really true? We have planned to install an Exchange Server 2016 and move all mail boxes to that server and uninstall Ex2013 but that was planned for next week so we are now in a bad situation. Does someone know if this update only works with CU 23 installed and if that is true, how can we minimize the threat for our EX 2013 ?Ex2013.png

3 Replies
They released the updates to some older/unsupported versions too: https://techcommunity.microsoft.com/t5/exchange-team-blog/march-2021-exchange-server-security-update...

Strongly advise you to follow the official guidance on this, which you can find in the article above and the references therein.
They covered some older 2016/2019 CUs for now.... nothing for 2013 so far - still requires CU23. At least they should allow customers to download older CUs in order to upgrade their old 2013 environment. We have some 2013 SP1 (CU4) servers which need to be updated to CU15 first, then CU19 and then to 22/23 due to .NET changes. Looks impossible to find links for these CUs...