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cyber-camp-2020-writeup

Cyber Camp 2020 CTF by SANS Institute Writeup

BM01

Category Points Difficulty
Binary 250 Medium

Solution

Downloading and extracting the program gives us a binary file, which we can run (preferably in a VM). Running it asks us for a name. Trying our name, we get “Hey name, nice to meet you, have a great day”. This just reeks of a buffer overflow question, and when we type in a really long string into the input (I used aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa), we get the flag.

Flag: AAAb1^jJdl&(&_;?>*!&~,$`