Hill Cipher SecurityThe basic Hill Cipher is vulnerable to a known-plaintext attack that attacks by key because it is completely linear algebra. An opposite site that intercepts n plaintext/ciphertext character pairs can set up a linear system that can be easily solved; if this will happen ...
The text in the input window is now transposed correctly. If you now click on "Solve", the cipher will still be solved. Apparently the previously loaded cipher is still stored somewhere. If you copy the transposed cipher and insert it again, "Solve" does not lead to any result anymore (...