I am able to bring down the permissions to very low by using the following commands.
Deny All to Login_Name
Deny Alter Any Login to Login_Name
Grant Execute master.sys.xp_ReadErrorLog To Login_Name
This will help in not allowing the login to create other logins, create jobs and others and will allow you to view the error log. However it is still able to Grant permissions to other Logins.
Can someone tell me how I can remove the Grant permission from the login.