Challenge "ElsieFour — Part 1" ¶
By: admin on Oct. 3, 2017, 6:37 a.m.
ElsieFour combines ideas of modern RC4 stream cipher, historical Playfair cipher and plaintext-dependent keystreams. It can be computed manually. Part 1 is a partly-known-plaintext challenge which provides 2 messages that were encrypted with the same key.