Two layers of base64
A first CTF warm-up. A note holds a string that decodes to more base64. Peel both layers with base64 -d and submit the flag in the HB{...} format.
Briefing
Flags in this practice set look like HB{some_words}. The challenge file is ~/challenge/note.txt.
Base64 uses A to Z, a to z, 0 to 9, + and /, and often ends in = or ==. If the output of a decode still looks like that, decode it again.
ctf-box · CTF warm-ups
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