PicoCTF Writeup – Bases
# Information:
CTF Name: PicoCTF
CTF Challenge: Bases
Challenge Category: General Skills
Challenge Points: 100
PicoCTF 2019.
# Challenge Description:
What does this bDNhcm5fdGgzX3IwcDM1 mean? I think it has something to do with bases.
Relevant hint: Submit your answer in our flag format. For example, if your answer was ‘hello’, you would submit ‘picoCTF{hello}’ as the flag.
# Writeup
Well by reading the title of the challenge “Bases” I immediately thought about Base 64 encoding. However, the = at the end of the string was missing. Despite the missing = I decided to try to convert the given string to UTF-8. To do that I used this online tool. The image below shows the obtained results:
After converting the given string I tried the flag structure as presented in the hint. And it was accepted!
Therefore, the flag is:
The image source can be found here.
Thank you very much for reading!
Cheers,
MRegra