falleen system
Description
We’ve managed to save magnetic tape from the bombarded remains of our capital. Our last hope in the fight against the dark side. But it is encrypted and even our sharpest engineers were unable to crack the code.
Could you acquire the flag and save our humble species with it?
- Author: tcs
- Attachment: magnetic-tape.dd
Solution
First things first, what file are we looking at. Running file on it, gives us the following answer:
magnetic-tape.dd: DOS/MBR boot sector; partition 1 : ID=0xee, start-CHS (0x0,0,2), end-CHS (0x3ff,255,63), startsector 1, 40959 sectors, extended partition table (last)
Ok, so we are looking at some sort of disk image. Running binwalk on it we can see, that there is a LUKS image inside, which we can extract using dd:
dd if=magnetic-tape.dd of=luks.part skip=2048 count=38878
LUKS is a way of encrypting disks on Linux, so we are going to need a key if we want to progress further. Luckily for us, we hit the jackpot on the first try. Running strings on the original file gives us tons of gibberish (as usual) and this:
The key is:down with the separatists
Using cryptsetup, we can open the partition:
cryptsetup open --type luks luks.part luks.opened
Mounting the opened partition, aaaaaaaaaand, nothing. I was puzzled for a minute. But luckily we hit the jackpot twice in a row. Where could they hide the flag if not in a file? Of cource it will be in the opened partition.
Running strings on it yields us the flag.
cd22{HIDDEN}