Solution: sudo /usr/bin/sudo must be owned by uid 0 and have the setuid bit set

sudo /usr/bin/sudo must be owned by uid 0 and have the setuid bit set

Got stuck by this error in Ubuntu 14.4 which is really painful as without sudo you cannot move forward … it will not allow you to do anything.

Solution:- Get in to Ubuntu Recovery Console
Start your computer and press and hold SHIFT key while booting. It will take you to the grub loader page as shown in image – 1.

Select and enter Advanced options for Ubuntu and from there select the kernel named as recovery mode as shown in image – 2.

select root – drop to root shell prompt as shown in image – 3

Now the file system is read only to Remount to Read Write run below command
# mount -o remount,rw /
# mount –all

then need to change the ownership for sudo
# chown root:root /usr/bin/sudo

give permisson for sudo
# chmod 4755 /usr/bin/sudo

it’s done … let’s see by restarting the machine
# shutdown -r now

Hopefully now you have solved the issue and sudo is working fine …

You may also like: Install and configure Jasper Report Server on Ubuntu Server