i have these files that i encrypted using luks a couple of years ago. and now i cannot seem to remember the passphrase/password. is there a way to bruteforce it?

You could try building python script that bruteforce the password

It depend on the encryption method of your password. If the algorithm is based on hashing , then it's impossible to decrypt password.

It will be slow, but you can try something like this :

#!/bin/bash
for PASSWD in $(cat passwords.txt)
do
    echo "$PASSWD"
    echo "$PASSWD" | cryptsetup open --test-passphrase crypted.img cryptmap - && break 
done

Not tested, but you get the idea.

(August 11, 2022, 05:12 PM)darkhero77 Wrote: i have these files that i encrypted using luks a couple of years ago. and now i cannot seem to remember the passphrase/password. is there a way to bruteforce it?

with Pexpect module

passparts = [["t", "T"], ["h"], ["e", "3"], ["_", ""], ["p"], ["a", "4"], ["s"], ["s"]]
possibilities = itertools.product(*passparts)
for x in possibilities:
    possible = "".join(x)
    print possible
    child = pexpect.spawn('udisksctl unlock -b /dev/sdc2')
    child.logfile = open("/tmp/mylog", "w")
    child.expect(".*")
    child.sendline(possible)
    child.expect(".*")
    print(child.before)
    child.expect(pexpect.EOF, timeout=None)
    print child.before
    print child.after

you can try to write your own app in python using multithreading

It looks like hashcat has support for bruteforcing luks so might be worth a look. Also found this article on it: https://www.forensicfocus.com/articles/bruteforcing-linux-full-disk-encryption-luks-with-hashcat/

I'm no expert in cryptography but executing a dictionary attack, and especially a brute force attack, against LUKS would likely take a looong time and require a significant amount of computing resources. I wouldn't bother unless I had a massive cluster with powerful hardware, personally. But I may be wrong.

(September 8, 2022, 04:23 PM)dongscorp Wrote: I'm no expert in cryptography but executing a dictionary attack, and especially a brute force attack, against LUKS would likely take a looong time and require a significant amount of computing resources. I wouldn't bother unless I had a massive cluster with powerful hardware, personally. But I may be wrong.

I mean no matter the strength of the cryptography it is still worth trying out at least top few thousand common passwords, maybe ones specific for your country etc. Intersection of people configuring luks and having terrible password is probably small but ya never know

what is it inside? Is it so important? :D