It is definitely good to have this pointed out since a lot of people do not realize it, and this was well written and clear.
From my standpoint, it tends to be irrelevant. Even if they cannot take full control of the server someone with even the SQL Server 2000 limited version of SecurityAdmin could cause so much mischief I would never hand it to someone I would not trust with full control server. At that point, I see the value of it in keeping honest people honest. Even if they know how to bypass it easily, they are faced with the fact that they are bypassing it. This reminds them that they are doing something that is properly in someone else's domain. For an trustworthy person, that is enough; for a non-trustworthy person even limited SecurityAdmin is far too much power.
Agreed, to a point. From a Principle of Least Privilege perspective, even if you trust someone to be a sysadmin, but they only should be doing the work of a securityadmin, you give them securityadmin. Only the permissions to do the job - no more, no less. And that's where this really busts audit controls.
K. Brian Kelley, CISA, MCSE, Security+, MVP - SQL Server
Regular Columnist (Security), SQLServerCentral.com
Author of Introduction to SQL Server: Basic Skills for Any SQL Server User
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