.dll that makes you admin

Okay, I know its probably not possible and im just being a idiot but if a .dll can change the sv_allowcslua 0 to sv_allowcslua 1 or vis versa then shouldnt it be able to alter a code to make yourself superadmin or owner rank status?

Please correct me if I'm wrong:

If I'm right, injecting is purely clientside
That's why you add 'cl' to the end of the open script command, it stands for cliant side
A dll, which you would inject into your client, wouldn't have any effect on the server.
I could understand a lua script doing this though
But then again, I'm a newbie too.

EDIT: I realized I totally contraticted myself.
Err, I meant a serverside lua script could, not a client side one, and unless the server is owned by owners that don't know how to own a server, you can't open serverside lua scripts.