PicoCTF2022 - file-run2

Description

Another program, but this time, it seems to want some input. What happens if you try to run it on the command line with input "Hello!"? Download the program here.

Information

Point Value: 100 points

Category: Reverse Engineering

Hints

1. Try running it and add the phrase "Hello!" with a space in front (i.e. ./run Hello!)

Solution

We download the program and add execute permissions the same we did in file-run1. To run the file with an input "Hello!", we add the input directly after executing/running it in the terminal. Running the program with this input gives us the flag. jackwin@COMPUTER ~ % ls -la
total 2
-rwxrwxr-x 1 jackwin admin 16736 Jan 1 00:00 fileRun1
-rw-rw-r-- 1 jackwin admin 16816 Jan 1 00:00 fileRun2
jackwin@COMPUTER ~ % chmod +x fileRun2
jackwin@COMPUTER ~ % ls -la
total 2
-rwxrwxr-x 1 jackwin admin 16736 Jan 1 00:00 fileRun1
-rwxrwxr-x 1 jackwin admin 16816 Jan 1 00:00 fileRun2
jackwin@COMPUTER ~ % ./fileRun2 Hello!
The flag is: picoCTF{F1r57_4rgum3n7_f65ed63e}

Flag