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WHEELER, pt. 2 Crack the ******

This challenge can be found on the inside of the cover of issue 7.

We are given the code: BYDBCQAAAAFnk8TL/uNcnt4A

We are told that the word "got compressed and lost its air".

The Decompression

The string looks to me like a base64-encoded string.

Decoding it with a base64 decoder works, but gives us raw binary data as output.

Using the hint, the next thing I try is decompressing the data. Using CyberChef I try a whole bunch of options but nothing works. The data does not have the proper headings that decompression algorithms expect.

The hint heavily points to zlib which implements the DEFLATE algorithm ("lost its air"). Hence I try decompressing using zlib and bypassing the header check (this is what the -15 is for).

import base64, zlib
decoded = base64.b64decode("BYDBCQAAAAFnk8TL/uNcnt4A")
decompressed = zlib.decompress(decoded, -15)
print(decompressed.decode())

We've got our word, nice!