Challenge Overview
A type of transposition cipher is the rail fence cipher, which is
described here. Here is one such cipher encrypted using the
rail fence with 4 rails. Can you decrypt it?
Download the message here.
Put the decoded message in the picoCTF flag format,
picoCTF{decoded_message}.
Solution
The provided a wiki page to where it shows how to decode this message manually, but I justed used cyberchef.
Encoded Message: Ta _7N6D49hlg:W3D_H3C31N__A97ef sHR053F38N43D7B i33___N6
Because it said in the description that it is the rail fence cipher with 4 rails I used rail fence decode with the key being set to 4.
This gaved the decoded message:
Flag: picoCTF{WH3R3_D035_7H3_F3NC3_8361N_4ND_3ND_4A76...}