A note shifted by thirteen letters
A short note looks like nonsense, but its word lengths and punctuation are intact. Rotate the alphabet by 13 with tr and read the flag hidden in the message.
Briefing
The challenge file is ~/challenge/intercept.txt. Spaces and punctuation are untouched, and the braces in the flag are still there.
ROT13 replaces each letter with the one 13 places later. Because the alphabet has 26 letters, the same command encodes and decodes. tr maps one set of characters onto another.
ctf-box · CTF warm-ups
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