(2014-06-25)
The according attack against the double-column transposition cipher was just described in the journal Cryptologia and is now implemented in CrypTool 2, based on the method presented in the article "Solving the Double Transposition Challenge with a Divide And Conquer Approach", Cryptologia, Volume 38, Issue 3 by G. Lasry, N. Kopal and A. Wacker.
Three new double-column transposition cipher challenges (level III) have been published, which don't contain the weaknesses of the old challenge:
- Double column transposition reloaded - Part 1
- Double column transposition reloaded - Part 2
- Double column transposition reloaded - Part 3
- Double column transposition - Part 1
- Double column transposition - Part 2
- Double column transposition - Part 3
- Double column transposition - Part 4
- Double column transposition - Part 5
You can find the according template in the Startcenter below the structure Cryptanalysis / Classical under the following name: "Dictionary attack on the Double Columnar Transposition Cipher".