PicoCTF 2017 – Substitute

Another day, another challenge.

Today’s blog post will explore solving the “Substitute” challenge inside of the PicoCTF.

Let’s get started.

Clicking on the challenge we see the following:

Clicking on the link we see:


Jumbled text…

Going back to the challenge and look at the hints we see:

Well the hint REALLY wasn’t that helpful.

Well using the hints we have with the title, we need to use a substitution cipher.

Doing a google search we have the following link.

Pasting the substitution cipher into the input box and pressing submit we see possible plaintext (original text).

Hmm… we see one that’s promising…


We found the flag!

Going back to the challenge and entering the flag and pressing Enter we have acquired 40 points!

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