cryptoProhard

PURPLE

taipanbyte

Task: Decrypt a ciphertext in 5-letter military groups with no key provided. Solution: Identify the PURPLE cipher machine from the task name and low Index of Coincidence, use the purple Python library with default/zero machine settings to decrypt, revealing the flag in the plaintext message.

$ ls tags/ techniques/
wwiiclassical_cipherpolyalphabetichint_in_namepurple_ciphercipher_machine
index_of_coincidencekey_from_tasknamepurple_machine_decryptioncipher_identification
🔒

Permission denied (requires tier.pro)

Sign in to access full writeups

Sign in with GitHub to continue. No email required.

$sign in

$ grep --similar

Similar writeups