The very first challenge ever completed for AlpacaHack was never released because we adjusted the difficulty for the first Crypto round. (Organizers' note)
Beginner Hint
- This challenge is in the Crypto (Cryptography) category.
- AlpacaHack currently features four main categories: Crypto, Pwn, Rev, and Web; everything else goes into Misc.
- Start by downloading the attached
a-fact-of-CTF.tar.gzand extracting it. - In
chall.py, the environment variableFLAGis read. This is the flag. - The flag is then transformed using prime numbers.
- The output of
chall.pyisoutput.txt. - The goal is to recover the flag from the value in
output.txt.