A 64-Year-Old Crypto Challenge

As you might have heard, Google has made the photo archives from Life Magazine available online. You could spend hours searching through those images for fascinating glimpses of history, and while I strongly encourage you to do so – and share anything really cool you come across – there’s something I’d like you to do, first.

Earlier, I posted some old photos of the FBI, in it’s early, “Bureau of Identification” days. While looking for a photo of the old, physical filing system at FBI headquarters – which I found, thanks to Google and Life – I stumbled across a pretty darn awesome photo from 1944:

There isn’t much information available about this image – “woman translating encoded message at FBI office” – but there are a few clues in the photo, which was (obviously) staged. It’s the FBI, remember, and 1944; on the desk are an (English) dictionary, as well as a copy of “Cassell’s New German Dictionary” and a German-English, English-German dictionary that looks well-used.

The sheet of paper includes both the “ciphertext” of the message, and the purported plaintext:

Americans are developing a new type plane propelled by rocket principle
Speed far in excess of any known
Planes already tested and in mass production
Soon will be ready for use in combat
New development may be used for regular propulsion or to give added (speed) in takeoff or in emergency (…)
Attempting to ascert(ain) (…) (det)ails.

A quick glance at the message – which I suspect was almost certainly produced for this staged photo, as propaganda – suggests the “code” is a very, very basic monoalphabetic substitution cipher. Mmm, the sweet, sweet smell of counterintelligence at work. 🙂

Your challenge, should you choose to accept it: provide any other details or insights into this message that you can. Tomorrow: Another, rather more interesting, cipher…

(edit 26 Nov: Even more awesome historical crypto goodness is now posted.)

Published in: Geekiness, General, History, Security | on November 25th, 2008| 5 Comments »

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  1. On 11/26/2008 at 11:15 am Craig Said:

    This message was written in english, then encoded.
    A real german message would be written in german, then cyphered.

    normally it would have to be decoded, then translated.

    So why would a report about american rocket planes already be in english?

  2. On 11/26/2008 at 11:38 am Dave Said:

    Looks to me like the alphabet is just step-shifted over to start at the letter “T” (T = A, U = B, V = C, etc.). I didn’t look any closer to see if there are any exceptions to the uniformity.

    My guess is a simple frequency of letters analysis would quickly tell you where to start. No math involved, just a couple of minutes of trial and error. A child’s puzzle, really.

  3. On 11/29/2008 at 10:40 am Saidhbhin Said:

    May I suggest a book that might interest you called “Between Silk and Cyanide” by Leo Marks. It talks about coding during the second world war, more specifically within the United Kingdom. The technology behind the codes is also nicely explained and not dissimilar to your next example. As everyone has already noted, this example is overly simplistic and staged.

  4. On 12/1/2008 at 12:47 pm Mark McCutcheon Said:

    This is a Caesar cipher with offset of 7, the simplest sort of substitution cipher. As others have noted, clearly a faked message.

  5. On 12/29/2008 at 9:42 pm Heath Said:

    It was photo for Life magazine, nothing more, nothing less. It was cool example of cryptanalysis for the laymen who read Life magazine at the time. I am sure it was not meant to convey anything more than making seasoned cryptanalysts grin.