PicoCTF - repetitions

Can you make sense of this file?

First, download the required file (enc_flag).

The file is formatted in the base64 format. We need to decode it multiple times in order to get the flag. Here is the Python code that does just that.

If you want to learn more about base64 type the following in a terminal.

man base64

import base64
import codecs

fp = [line.strip() for line in open("enc_flag")]

t = "".join(fp)
print(t)
print("--------------------------------")

res = base64.b64decode(t)
print(res)

ATTEMPTS = 5

for i in range(0, ATTEMPTS):
    res = base64.b64decode(res)
    print(res)

At first, we read the contents of the file. Then, we join them as one string and decode the string using b64decode. Finally, with the help of the loop and the right length we can get the flag.

Nice one, you've got the flag!