Can access to a heroku postgresql DB be restricted to it's heroku app ONLY?

Question

I've recently migrated an application from heroku to amazon-ec2 because of recomendations from a security consultant. Yet, he didn't know deeply heroku and the doubt remained.

Can access to a Heroku PostgreSQL DB be restricted for it to be accessed only by the application?

Would you recommend Heroku for security critical applications?

Answer 1

This is a deceptively complex question because the idea of "restricted so that it can be accessed only by the application" is ill-defined. If your ultimate goal is simply to keep your data as secure as possible, then Heroku vs. AWS vs. physical servers under lock and key involves some cost-benefit analysis that goes beyond just how your database can be accessed.

Heroku limits database access via authentication. You share a secret (username/password) between the database and the application. Anyone who has that secret can access the database. To facilitate keeping the secret secret, all database access is or should be over SSL.

There are other ways to restrict access in addition to authentication, but many of them are incompatible with a cloud-based approach. Also, many of them require you to take much more control over the environment of your servers, and the more responsibility you have on that front, the bigger the chance that issues totally separate from who can hit the postgres port on your database will sink you.

The advantage in using AWS directly instead of through a paas provider like Heroku is that you can configure everything yourself. The disadvantage is that you have to configure everything yourself. I would recommend you use AWS over a managed service only if you have a team of qualified and attentive sysadmins to configure, monitor and update your environment. Read Heroku's security policy page. Are you doing at least that much to protect your servers in your own configuration on AWS? If not, then you might have bigger problems than how many layers of redundancy are in place around your database.