Egg 3: Lego Stego

Challenge:

You intercepted a message sent by a nerd from the office nearby. On first sight, there’s nothing suspicious in it. However, you are almost sure that something secret must be hidden in it. Can you find out what?

file

Solution:

we open the file in lego builder app link and see the following model:

we see some barcode-like pattern near the bottom, could be binary

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01010110101010100101
10100101000011001010
01101010111001011001

..but this leads nowhere..

aha! if we rotate the model we see that the dots on the top are also different heights:

we transcribe the heights:

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214124434323432332113221
121341111313213121331211
414113143142314114341211

..can’t make any sense out of it..

We go back to the model and pull apart the different layers, and yes! a QR code is revealed:

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