break grub password

hi,

Is there is any method to break grub password.

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Hash: SHA1

Break it? Like corrupt it? If you put in an invalid value then it
obviously won’t work. If you want to break through it then that’s not
very easy normally (assuming all you have is the ability to boot through
Grub) but if you have a CD/DVD/etc. and some other way to boot the system
you could just skip past it, or remove it from the conf file, or change it
to a value you like, or run it through a brute force technique to find out
the original password.

Good luck.

angathan wrote:
> hi,
>
> Is there is any method to break grub password.
>
>
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angathan wrote:
> Is there is any method to break grub password.

Remove or reset the grub password from the configuration if you
have physical access to the machine? Easy. Boot any live/rescue medium
and change it.

Recover the used password back into plaintext if you have physical
access to the machine?

Harder but possible. It’s basically a salted md5-hashed password.
Fun reading: “man mkpasswd”, “man 3 crypt” and rainbow tables.

Kind regards,
Andreas Stieger