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**This technique has been deprecated and should no longer be used.** The source 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 source /path/to/filename [arguments] or .**This technique has been deprecated and should no longer be used.** /path/to/filename [arguments]. 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.