This was driving me batty. I had an issue with one of my linux webservers and it needed to be restored from a backup. Upon restoring the linux server I found my account that I had setup for sudo access no longer would accept the ’sudo su’ command or any sudo command for that matter. I was getting and error that read “Sorry, sudo must be setuid root“.

As I had removed the root account from accessing ssh I had to log into the physical server (lucky it’s just next to me!)

It turns out for some reason after the restore sudo had the wrong permissions.

To fix it was quite simple but took me ages to track down! (Helps if you know exactly what to search for)

I logged in as root and entered the following

chmod 4111 /usr/bin/sudo

All was fine in the land of oz after that!