This is basic security advice, but a surprising number of developers embed the SQL Server system administrator (sa) account credentials within their application connection strings.  This leads to two major issues.

·         The account credentials are visible to anyone who has access to the application's source code.

·         Should the website be compromised the malicious user may be able to delete tables, drop databases and be able to do all manner of other undesirable things.  It is, therefore, highly recommended that a new SQL Server user account be created for the Internet user.  This user should only be given access to the objects they are going to need to access.  If they only need read access for a table for example, then they should only be given SELECT permission and not INSERT, UPDATE or DELETE permission.

The use of stored procedures is highly recommended as a means of improving security because then the user only needs to be given EXEC permissions on the stored procedures they need to use.

Alternatively, it is possible to use Windows authentication for the SQL Server access, in which case for applications using anonymous access,, the IUSR_machinename could be configured as a SQL Server user and given the minimum level of object access.