Question: How to Change Ubuntu Password Without Knowing It?

From the official Ubuntu LostPassword documentation:

• Reboot your computer.
• Hold Shift during boot to start GRUB menu.
• Highlight your image and press E to edit.
• Find the line starting with “linux” and append rw init=/bin/bash at the end of that line.
• Press Ctrl + X to boot.
• Type in passwd username.
• Set your password.

How do I reset my root password?

1. Reset Lost Root Password from the Grub Menu

1. Now press e to edit the commands.
2. Press F10 .
3. Mount your root filesystem in read-write mode:
4. Once you are done, type:
5. Open the terminal, and type the following command to become root:
6. At this point we need to jail ourselves in the “mnt/recovery” directory.

How do I change a user password in Ubuntu?

How to Change sudo Password in Ubuntu

• Step 1: Open the Ubuntu command line. We need to use the Ubuntu command line, the Terminal, in order to change the sudo password.
• Step 2: Log in as root user. Only a root user can change his/her own password.
• Step 3: Change the sudo password through the passwd command.
• Step 4: Exit the root login and then the Terminal.