title: sudo: /etc/sudoers is world writable in Ubuntu
body: <p>I use <code>chmod a+x /etc/sudoers</code> in <strong>ubuntu</strong> user which make me regret...</p>
  
  <pre><code>ubuntu@VM-250-150-ubuntu:~$ ll /etc/sudoers
  -rw-rw--w- 1 root root 781 May  5 11:12 /etc/sudoers
  </code></pre>
  
  <p>And then I can<code>t use</code>sudo`</p>
  
  <pre><code>ubuntu@VM-250-150-ubuntu:~$ sudo
  sudo: /etc/sudoers is world writable
  sudo: no valid sudoers sources found, quitting
  sudo: unable to initialize policy plugin
  </code></pre>
  
  <p>I don't have any <strong>root password</strong> so I try <code>pkexec chmod 440 /etc/sudoers.d</code> to fix it.</p>
  
  <p>But it has another problem,I input the <strong>ubuntu`s password</strong>:</p>
  
  <pre><code>ubuntu@VM-250-150-ubuntu:~$ pkexec chmod 440 /etc/sudoers.d
  ==== AUTHENTICATING FOR org.freedesktop.policykit.exec ===
  Authentication is needed to run `/bin/chmod' as the super user
  Authenticating as: ubuntu,,, (ubuntu)
  Password:
  polkit-agent-helper-1: error response to PolicyKit daemon: GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: No session for cookie
  ==== AUTHENTICATION FAILED ===
  Error executing command as another user: Not authorized
  
  This incident has been reported.
  </code></pre>
  
  <p>Friends, can you help me without reinstalling, please? I am regret so much....</p>
  
  <p>And I hope my story can help others. Don<code>t change the privilege of</code>/etc<code>optionally. It</code>s better to use <code>sudo visudo</code> or edit a file in <code>/etc/sudoers.d</code>.</p>