3rd Party Authentication with Camunda


I’ve got the following problem: I want to use a camunda process to access a SQL Server.

In order to do so the process needs to authenticate itself against the SQL Server, but I can’t use the user who runs the Camunda engine to do so (Because this user might not have the rights to access the sql server).
I can’t store the credentials of the DB-User in a Java file either, because the server which hosts camunda is accessed by several people and this would be a security issue.

Would it be possible to use the user credentials of the user who starts the process in the tasklist, if camunda is connected with an active directory?
Is there any other option to achieve this goal?