T1153

The <code>source</code> command loads functions into the current shell or executes files in the current context. This built-in command can be run in two different ways <code>source /path/to/filename [arguments]</code> or <code>.**This technique has been deprecated and should no longer be used.** /path/to/filename [arguments]</code>. Take note of the space after the ".".

Without a space, a new shell is created that runs the program instead of running the program within the current context. This is often used to make certain features or functions available to a shell or to update a specific shell's environment.(Citation: Source Manual)

Adversaries can abuse this functionality to execute programs. The file executed with this technique does not need to be marked executable beforehand.