Banjo

Overview

Overall difficulty for me (From 1-10 stars): ★☆☆☆☆☆☆☆☆☆
Challenge difficulty: Easy

Background

Author: @JohnHammond#6971

Oooh, that classic twang! The banjo is one of my favorite strings instruments!

Download the file below.

Attachments:

┌──(root🌸siunam)-[~/ctf/NahamCon-EU-CTF-2022/Warmups/Banjo]
└─# file banjo.jpg 
banjo.jpg: JPEG image data, JFIF standard 1.01, aspect ratio, density 1x1, segment length 16, progressive, precision 8, 366x400, components 3

Find The Flag

As the challenge’s background suggested, we need to use Linux command strings!

┌──(root🌸siunam)-[~/ctf/NahamCon-EU-CTF-2022/Warmups/Banjo]
└─# strings banjo.jpg | grep -oE 'flag{.*?}'
flag{ce4e687e575392ae242f0e41c888de11}

Note: In here, I used strings command, then I piped (|) it, or I let the output of the strings command to the next command, which is grep. And grep -o flag is to find only match result, then -E flag is to use regular expression(regex) to find the flag.

Found it!

Flag: flag{ce4e687e575392ae242f0e41c888de11}

Conclusion

What we’ve learned:

Linux List Strings via strings