Description
BASE unknown
Description: IVFU662CIFJUKXZTGJPWG2DBNRWH2===
Resolution
It seems to be a string encoded into base64, but without lower letters.
With the challenge title as hint, we tried base32.
You’ll say “ABC…XYZ + 012…789 = 26 + 10 = 35 and not 32 ? WTF!”
In fact only numbers 234567 are used : 26 letters + 6 digits = 32 😉
We opened our dear python shell:
$ python
>>> import base64 >>> text = 'IVFU662CIFJUKXZTGJPWG2DBNRWH2===' >>> print base64.b32decode(text) EKO{BASE_32_chall}
Flag was : EKO{BASE_32_chall}