sudo does not require password authentication for subsequent executions

Issue

sudo does not require password authentication for subsequent executions

• A sudo rule explicitly requires an user to supply a password to run any command:

  bob ALL=(ALL)       PASSWD:ALL
  

• sudo asks for password the first time. It does not request the user to authenticate for subsequent access:

  [bob@server1 ~]$ sudo su - root
  [sudo] password for bob: 
  [root@server1 ~]# exit
  logout
  
  [bob@server1 ~]$ sudo su - jane
  [jane@server1 ~]$ exit
  logout
  
  [bob@server1 ~]$ sudo su - root
  [root@server1 ~]# exit
  logout
  
  [bob@server1 ~]$
  

• It is a security requirement that the system must require re-authentication when using the "sudo" command.