IMHO there is a security feature in DNN that is not used enough, and it is really easy to implement. The feature I am talking about is the use of the upgradeConnectionString. This was added way back in version 2.?? (2.0.12 I think) and it is still not used by most users. What this feature allows you to do is run DNN under a less privelege account, and the upgradeConnection user is for all installation DB functions. Below is instructions on how to implement this feature.
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1) Create 2 users in the database with the following permissions.
a)
PortalUser -- public b)
PortalAdmin -- public
-- db_securityadmin
-- db_ddladmin
-- db_datareader
-- db_datewriter2) Use PortalUser in the <SiteSqlServer> key. This key is under <appSettings> in DNN3 and under <appSettings> and connectionStrings> in DNN4.
3) Use PortalAdmin in the <upgradeConnectionString> key which is under the SqlDataProvider section. The same place dbowner and objectQualifier are set.
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That is all there is to using this security feature. The PortaUser will only have access to execute Sprocs (3.2.2 and previous, 4.0.3 and previous) and Sprocs and User Defined Functions (3.3.3+ and 4.3.3+) and not have any direct table access. The PortalAdmin user now has all the permissions the PortalUser would have had if upgradeConnectionString was not used ,and PortalAdmin is only used during the install process (including module installs). As a final part of the installation process, if the upgradeConnectionString is being used the install makes sure public has execute permissions for all stored procedure and execute/select permissions based on type of User Defined Function (Scalar or Table).
By implementing the above security feature you will make you DB Admins and Security Group extremely happy. I know that when we used DNN before the upgradeConnectionString was implemented, we ran the install with the user having DBOwner access, and then we updated the user permissions to only have public access and manually ran a script to grant public execute permissions on all the Sproc's. As a matter of fact, that SQL script was used as the basis for the code that the install uses to grant the appropriate permission to public and later also to User Defined functions :-).
I am in the process of upgrading the installation documentation to reflect the use of the upgradeConnectionString to make DNN more secure, but until that is completed you can use this blog to help you implement this feature.