The SIGABA CSP-889 was a highly secure encryption machine used by the US for strategic communication in WWII. In this series of challenges, you are provided with a ciphertext and a partially-known plaintext, here with the length of 320 and 120 characters.

Update June 2021: We replaced the used key (and this changed the ciphertext) since a part of the previous used key was leaked in the newest SIGABA template of CrypTool 2.
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