GUM Workbench is an independent application which runs on Windows desktops. GUM Workbench will not use the internet during normal usage and is therfore not affected by security breaches of servers and Internet browsers.
GUM Workbench uses for its calcualtion no open-source-libraries. Therefore GUM Workbench is not affected by security breaches found in these libraries.
Some extensions of GUM Workbench are using the script language Python. Security breaches found in Python might therefore be relevant to GUM Workbench. Up to now, no relevant security breaches are known in the used versions of Python.