Consider the following scenario:
You have an AlwaysOn Availability Group (AG) in SQL Server 2017 with database Distributed Transaction Coordinator (DTC) support enabled.
During Availability Group failovers, SQL Server internal DTC State for all the databases in the AG is first stopped, and then all the active transactions for all the databases of this availability group are killed.
However, before the active transactions are killed, if these transactions try to access the stopped DTC State, a memory corruption may occur.
This happens because the transactions are trying to access the memory that has already been deleted.
This issue is fixed in the following cumulative update for SQL Server:
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Learn about the terminologythat Microsoft uses to describe software updates.