Thursday, 16 October 2014

NUS SoC Hacking Challenge 7 - On Your Own!

Level 7 - Final Level of the Hacking Challenge!

Credits goes to my colleague Jan Teo YZ for completing this stage. 

The Starting point of Level 7 Stage

    Hmm, a picture, two buttons and an input field. A quick search on “Symbol ciphers” gave the above image.

Something similar to the first image.

Using the Freeman’s cipher, we can decipher the picture 

Upon deciphering the symbol against the characters, we get the above sentence "YOU HAVE ALMOST REACHED HEKA"

Trying the phrase “You have almost reached Heka” doesn’t give us access, let’s click on the “download” button and see what it gives us

Just a piece of text file with nothing on it (of course, its invisible)

Lots of white spaces and tabs… hmm. A quick search through google revealed the above.

Aha... Whitespace. Trying it out in SNOW, compiling as the Whitespace programming language gave no results.(A Segmentation Fault occurs when you try compiling it) After trying for a long while with no results, I had to resort to asking NUS for tips.

It finally hits me. Going back to the document, I replaced all spaces with zeros and tabs with ones and separated them in sets of 8 (a byte)

Pasting them into a binary to ASCII converter

We get the phrase “Well done! Orb secured.” Concatenate both phrases and we get “You have almost reached Heka Well done! Orb secured."


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