Hacking password protected “single user” mode in Linux
Single user mode can be protected by appending this line in /etc/inittab
if this line is present in the /etc/inittab – the machine will ask for root p@$$word
while booting p@$$ this kernel parameter –
by p@$$ing this parameter, I am saying to the kernel, “rather than starting /sbin/init and proceed with the usual /etc/rc.d/* procedure, just simply give us a shell”. That means:
NO p@$$word checks
NO filesystem checks
NO startup environment
…as no filesystem checks has been made, the filesystem will be in read-only mode.
Now give this command, to make root filesystem writable.
mount -o remount, rw /
Once the p@$$word is reset or done anyother thing you wanted to do, DO NOT REBOOT.
mount -o remount, ro /
NOW PRESS THE RESET BUTTON
You can also see the video of this post