Summary#

This challenge focuses on the ROT13 cipher, a simple substitution cipher that shifts each letter by 13 places in the alphabet.
The goal is to decode the ciphertext cvpbPGS{abg_gbb_onq_bs_n_ceboyrz}.

You can solve it using any online ROT13 tool, such as rot13.com, or by applying the shift manually.

Analysis#

This challenge is quite similar to Mod 26

UIisng the ROT13, we get the flag : picoCTF{not_too_bad_of_a_problem}

⚡ Raikiri

🎉 Flag pwned! The ROT13 cipher has been successfully decoded.

💡 TL;DR / Lesson Learned

ROT13 is a Caesar cipher with a fixed shift of 13.
Applying it twice returns the original text, a simple yet elegant example of modular arithmetic in action.