Python vs NodeJS web applications from a security point of view
Disclaimer, I'm not super expert on the topic, but I have worked a bit with both Node and Django.  
I'd say that it pretty much depends what you're doing and how you set everything up, but with Django you're pretty much forced to set it up on Apache/Gunicorn (w/ NGinx) so you have that extra layer there that you can use to have an additional layer of security, and Django has a lot of built in packages to help with authentication / users / etc.  
But honestly it boils down to how well structured your application is.  I'd personally prefer python for building a secure application as for me it's easier to wrap my head around OOP logic in python moreso than trying to structure all your callbacks correctly in node.
I am planning to build a web application which is security critical and I need to decide what technology to use on the back end.
The options I am considering are Python (mostly with the Django framework) and NodeJS (possibly with express.js). From the security point of view I would like to know the pros and cons of using each of these technologies.