Multicode
We intercepted a suspiciously encoded message, but it’s clearly hiding a flag. No encryption, just multiple layers of obfuscation. Can you peel back the layers and reveal the truth? Download the message.
Download message.txt.
The text looks like Base64, so decode it with CyberChef.
The result looks like hexadecimal values, so decode it from hexadecimal.
The decoded text contains percent-encoded sequences, so apply URL decoding next.
The result resembles a flag, but the letters are shifted. Try different rotation values to recover the flag.
A rotation of 13 (ROT13) reveals the flag.
This post is licensed under CC BY 4.0 by the author.