Number Cruncher

Description#

Our brand new number-crunching program makes data impossible to retrieve! To prove it, try and decode this crunched up flag!

Attachment: cruncher, flag.crunched

Solution#

From the description, we know that the flag has been encrypted and has been outputted to flag.crunched.

By looking at the encoded flag, we can see that it is in hex format.

By using Ghidra, we can take a closer look into one of the functions named crunch which seems to be the function that encrypts the flag. From the function, we can see that the input is being xored ^ by the hex key b3.

Therefore, we can go to CyberChef to decode and decrypt it to get the flag.

Flag#

HTB{uncrunch1ng_d4t4_f0r_fun_n_pr0f1t}