Challenge 6 alternative method

[neilmunday]

Hi Nicolaas,

If you're interested, here's how I solved challenge 6...

It is clear that decryptor is looking for a file so run it like so through strace:

strace -e open ./decryptor

When examining the output of strace we can see the following:

open("phantom_bits", O_RDONLY) = -1 ENOENT (No such file or directory)

Therefore rename e85150c59040bbfe9b14ee0f5fa9e2cf to phantom_bits and run the program again.

For the second stage use the faketime utility to intercept sys calls from Final_Stage for the date/time:

faketime '1986-01-24 00:00:00' ./Final_Stage

Regards,

Neil.

p.s. Thanks for sharing your write-up - I would never have found challenge 11!

[NicolaasWeideman]

Hi Neil

Ah, that does seem like a much easier solution.
I'm beginning to learn that I should spend more time searching for the best/easier solutions, than immediately going for the old faithful.

Did you upload your write-up somewhere?

Thanks!

Nicolaas

[neilmunday]

I only found out the HackFu challenges about 5 days before the deadline so I never submitted any solutions. I didn't manage to do all of them so I haven't written them up.

I also came across this person's write-up which you might be interested in: https://github.com/jasonbrackman/hackfuchallenge2017

I will keep an eye out next year!