Hi HN.<p>As a hobby, I have been studying Kryptos K4, a classic unsolved code. Kryptos is a puzzle sculpture dedicated by its creator in 1990. It contains four encrypted messages. Three have been decoded (K1 to K3), and the last one, K4, remains undeciphered.<p>Like many others, my attempts to solve it using classic cryptanalysis attacks have failed. However, I have recently discovered a pattern that may indicate a distinctive encryption technique. To test this idea, I created “K4nundrum”, an open-source tool written in Go: <a href="https://github.com/glethuillier/K4nundrum">https://github.com/glethuillier/K4nundrum</a><p>So far, this tool has revealed that K4 may result from combining ciphertext segments with the letters “W.” It will be continuously updated to provide additional insights on the encryption technique(s) employed for K4.<p>You can read this approach in more detail here: <a href="https://guyomel.hashnode.dev/a-fresh-perspective-on-kryptos-k4" rel="nofollow">https://guyomel.hashnode.dev/a-fresh-perspective-on-kryptos-...</a><p>If you are interested in classic ciphers, I hope you will enjoy using this tool and even contribute to it.<p>I appreciate any feedback.<p>Thank you.