You can obtain the operation_id of an executing SSIS package in several ways.
One way is from the All Executions report built into SSMS:

Another way is to use my (free) utility Catalog Reports which is a SQL Server Reporting Solution (SSRS) solution that allows you to view much of the information contained in the Catalog reports built into SQL Server Management Studio (SSMS). It’s shown here running on SSRS 2016 inside the Microsoft Edge browser:

Once you have the operation_id value, simply plug it into the stop_operation stored procedure and execute:
exec SSISDB.[catalog].stop_operation @operation_id = 24The stop_operation stored procedure runs for a few seconds (typically less than 15 seconds) and stops the execution of the SSIS package. SSIS packages that have been stopped are listed with “Canceled” status. You can see operation_id 19 was stopped in the screenshots shown above.
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