Look Harder – 50
There are rumours that in the Great Sahara Desert, a great treasure has been buried deep inside the ground, but the map for the exact location of the treasure over the years, has not been preserved properly. You have got hold of the map, but it looks nothing more than a plain white sheet of paper. Can you make sense out of it ??
The image appears to be all white, except when titling the screen there is a faint contrast between two similar colours giving the outline of what seems to be a QR code.
Opening the image up in GIMP we see the image is in indexed mode so lets change the main colour from faint yellow to black.
Windows -> Dockable Dialogs -> Colourmap.This makes our QR code visible enough to scan and get the flag.
Interstellar – 150
Dr. Cooper, on another one of his endless journeys encounter a mysterious planet. However when he tried to land on it, the ship gave way and he was left stranded on the planet. Desperate for help, he relays a message to the mothership containing the details of the people with him. Their HyperPhotonic transmission is 10 times the speed of light, so there is no delay in the message. However, a few photons and magnetic particles interefered with the transmission, causing it to become as shown in the picture. Can you help the scientists on the mothership get back the original image.
The image appears to be corrupted in some what – modified heavily from the original. It almost looks like there is destructive interference or value inversion, because I can see a tree and what looks like the moon, but a tree is definitely not purple and white.
After playing around with many different tools, I came across
Colors -> Components -> Decompose. This separates an image into its channel components, in this case we want RGBA. On the red channel we can clearly see our flag hiding in plain sight.
The Karaboudjan – 150
Captain Haddock is on one of his ship sailing journeys when he gets stranded off the coast of North Korea. He finds shelter off a used nuke and decides to use the seashells to engrave a message on a piece of paper. Decrypt the message and save Captain Haddock. ->-.>-.---.-->-.>.>+.-->--..++++. .+++. .->-.->-.++++++++++.+>+++.++.-[->+++<]>+.+++++.++++++++++..++++[->+++<]>.--.->--.>.
The following symbols are Brainfuck code, which when executed output the following data, shown here as a hex string.
ffff fcff 0001 fefe 0202 0505 ffff 0903 050d 121c 1c60 5efe 00
I did not work out how to massage this data into a key for the zip file. Instead, I used a tool called
fcrackzip to enumerate through a dictionary of words to try and crack the zip file. Luckily, the password for the zip was an English word.
fcrackzip clue.zip -D -p english.txt -u
The pcap file inside the zip just has a simple packet which has the flag hidden in the frame.