HSCTF_2017: KE1TH

Category: Reversal Points: 200 Description:

Keith recently coded a small authorization software for his/her computer to hide personal files. Unfortunately, he/she hit his head and forgot his/her password. Now he/she must reverse engineer his/her software to regain his/her password.

Write-up

It's just a small reversing challenge where they already given everything we need. IV? Check. Key? Check. Ciphertext? Check.

Solution

$ ./solve.py 
Flag: this_was_a_short_and_easy_problem_2B3F5AC0

Therefore, the flag is this_was_a_short_and_easy_problem_2B3F5AC0.