How to Secure our Oracle Databases

How Secure can we make our Oracle Databases??

This is a routine question that runs in minds of most database administrators.  

HOW SECURE ARE OUR DATABASES. CAN WE MAKE IT ANYMORE SECURE.

I am writing this post to share my experience and knowledge on securing databases. I personally follow below tips to secure my databases:

 1. Make sure we only grant access to those users that really need to access database.

2. Remove all the unnecessary grants/privileges from users/roles.

3. Frequently audit database users Failed Logins in order to verify who is trying to login and their actions.

4. If a user is requesting elevated privileges, make sure you talk to them and understand their requirements.

5. Grant no more access than what needed.

6. At times users might need access temporarily. Make sure these temporary access are revoked after tasks are completed.

7. Define a fine boundary on who can access what??

8. Use User profiles / Audit to ensure all activities are tracked.

9.  Enforce complex password. Here is the Link on how to do it 

10 Use Triggers to track user activity.

11. Make sure passwords are encrypted in applications, this can be potential threat if you application code has been compromised.

12. Add password to your listener.

13. Allow access only from needed/known servers/clients. Use Valid_node_checking Link on how to restrict access to servers/clients.