We are given two hints to start with - an image and a pice of text:

In a far away land, shaped like the head of a pwnie,
dem natives found a way to communicate in secret (sorta)
bearly advanced esoteric RF technol0gies...
I once befriended a bear in a bar on pwnie island.
He kept rambling on about Richard Stallman, and some treasure...
He handed me this napkin, and said we could speak through the ether
I captured this message data to a GNU Radio complex data file...
Maybe its a secret to the treasure!?!?

Demodulate the key

Hint

So as the hint says, we just have to fire up GNU radio and construct the inverse operations from the ones performed.

Hint

Running the design gives out flag.jpg:

Hint


ebCTF 2013 - Net 400 (Figuurzagers)

01 August 2013 by mf

Writeup for Network 400 task.

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SigInt 2013 - Pwning 400 (crash)

01 July 2013 by mf

Non-standard format string task.

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Defcon CTF Quals 2013 - \xff\xe4\xcc 200 (blackjack)

30 June 2013 by mf

Solution for penser.

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Defcon CTF Quals 2013 - \xff\xe4\xcc 300 (linked)

30 June 2013 by mf

Solution for linked.

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Defcon CTF Quals 2013 - \xff\xe4\xcc 400 (penser)

30 June 2013 by mf

Solution for penser.

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