EasyCTF_2018: Format

Category: Binary Exploitation Points: 160 Description:

Go to /problems/format on the shell server and tell me what is in flag.txt.


We are given two relevant files, format and format.c. This is a really easy challenge where you just have to format string your way out. However, as it is a 64-bit binary, certain tricks have to be played to get the password :)

$ ./format
Enter your name: %7$llx
Your name is: 1eb89e5c00000000

Enter your secret password (in hex)

Therefore, the flag is easyctf{p3sky_f0rm4t_s7uff}.