Newbie question on connect internal

This may be a dumb question, but bear with me.

When the svrmgrl program is invoked, it is possible to logon by using "connect internal".
This effectively means that any user could connect to a database by doing this.

My question is :
Do you change the permissions on the svrmgrl executable to prevent this, or is there some other method?

TIA

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Michael McGarrigle   	 Michael.McGarrigle_at_BarwonWater.Vic.Gov.Au
Information Systems      Barwon Water
61-67 Ryrie St Geelong   Phone: +61 352 262326
Victoria 3220 Australia  Fax:   +61 352 218236