I installed some software by running its install script with

sudo ./install.sh

After the installation all the accounts on my Ubuntu laptop can gain root access by simply issuing the command sudo -s, even the standard (non administrator) account. Also there is no password prompt when issuing the command sudo -s.

My /etc/sudoers looks like this:

Defaults    env_reset

Defaults    secure_path="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"



# Host alias specification



# User alias specification



# Cmnd alias specification



# User privilege specification

root    ALL=(ALL:ALL) ALL



# Members of the admin group may gain root privileges

%admin ALL=(ALL) ALL



# Allow members of group sudo to execute any command

%sudo   ALL=(ALL:ALL) ALL



# See sudoers(5) for more information on "#include" directives:



#includedir /etc/sudoers.d

ALL ALL=(ALL) NOPASSWD:ALL