The Exchange product group released the November 2026 update for Exchange Server SE. As mentioned in the previous Security Updates post, the October security updates were the last updates for earlier Exchange Server versions.
The vulnerabilities addressed in this Security Update are:
The Security Update is linked below:
Issues resolved
- The issue with the RPC endpoint mapper that appeared after installing the October updates for Windows Server is addressed in the November updates for Windows Server. If you created the registry keys to raise the new default RPC limit, you can only remove these registry keys after installing the November updates for Windows Server.
Notes
- Security Updates are cumulative, and you only need to install the latest SU for your CU.
- If you deployed Exchange Management Tools to manage your on-premises Exchange Servers, or installed the tools after removing the Last Exchange Server for recipient management, we recommend applying the Security Update.
Finally, as with any patch or update, test it in a test environment before deploying it to production. However, we do not recommend waiting for regular maintenance cycles for security updates; a more agile approach is preferable, and the ratings indicate the urgency level.
Related