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My favourite Enigma message - as told to me by a tour guide at Bletchley Park - was thought to be a stream of indecipherable gibberish.

Until a WREN noticed that the message never contained the letter Z.

One weakness of that generation of Enigma was that it could not self-encode a letter. That is, A was never encrypted to A.

This had no letter Zs. A statistical improbability. Unless, so she reckoned, the entire message consisted of only the letter Z repeated.

Apparently, their best guess was that a bored soldier sent a stream of Zzzzzz to a friend. That was enough to crack that day's key.

Of course, every guide at Bletchley has a range of stories they tell credulous geeks. But it is a delightful tale of how OpSec is everything.



>One weakness of that generation of Enigma was that it could not self-encode a letter. That is, A was never encrypted to A.

That's not just "a weakness", that is afaik the central weakness that allowed the breaking of the enigma in the 30s by Polish codebreakers.


I didn't know about this thanks for the tip.

https://www.bbc.com/news/magazine-28167071


> A statistical improbability.

Probably more of a flaw if your message is in German or US English.


Pretty sure Germans use Chrrrr.


Doesn’t matter. You’re interpreting it as some stupid message, when it’s literally a bored 19 year old pressing which ever key is most convenient again and again and again and again… simply to create bogus radio traffic.

There were tons of bogus messages where the wheels were set to whatever German teenager’s favorite four letter swear word was.


IIRC there was one German operator who used his sweetheart's initials over and over as the combination allowing for decryption.


I believe these single letter "messages" were useful in quickly determining the day's setup, and maybe wiring diagrams, but I'm not sure about the last part.


Wasn't it all messages ending with "heil hitler"? I mean that could be the operator's sweetheart in a way.


Sort of, but that's a massive oversimplification. The bomba machines needed shorts "cribs" of expected plain text to search against, like "heil hitler" as you mentioned, and I think usually they went after the standard start of the day weather report. But the bomba only can reduce the search space, it doesn't produce the answer, and analysts still need to manually break it.

So yes but it was hard so they also took advantage of operator error where ever possible.

This stack exchange explain it well: https://movies.stackexchange.com/questions/30332/why-does-th...


I wonder if they had the passwords as post-its next to the machine…


Post-it only got invented in 1968 unfortunately.


Back then, post-its were called slates.


Must be human nature. When I used an enigma machine at a museum, the first thing I did was try to make it light up with a 4 letter word. It does help that 4 letters of ciphertext is easier to remember :)


> When I used an enigma machine at a museum

Did you use the one at Bletchley park too?

I tried to go back to use it again but it had been stolen and the one they had was locked away behind glass.

https://drenigma.org/2017/10/16/the-stolen-enigma-machine/


I'd love to visit Bletchley Park some day, but no. It was at the (United States) National Cryptologic Museum. They actually had 2 enigma machines you could play with (IIRC different variants so messages on one weren't compatible with the other).

That sucks that someone would steal it. Being able to go hands on with one is such a cool experience.


I can imagine some “adversarial gloves” (with regard to https://adversarialfashion.com/) for VisionOS which allows someone who’s not wearing the goggles to have their hand gestures interpreted in various ways, including the ability to make an obscene gesture -- localized to the goggle-wearer’s location, of course -- at said goggle-wearer to be interpreted as the system-configured shutdown gesture. I’m inclined to agree with you that it must be (read: I hope it is) human nature, given my enjoyment of machine exploits. Makes me wonder about https://news.ycombinator.com/item?id=36470438 (“A brief history of insults”). (I know I’ll be likely to use my goggles-computer exclusively in private places.)


Did you post this on the wrong thread?


Maybe there will be an Enigma machine app for VisionOS


I did not. I’d considered whether it was off-topic or not and concluded that it was not given the direction of discussion up to the point of my comment. We’re several comments deep after one tangent from “enigma machine exploits” to “obscenities with enigma machine exploits” and my tangent to “obscenities with hypothetical-but-not-yet-implemented machine exploits”. I can understand that it seems out of place, though I also disagree that it is out of place.

(Really, the biggest reason I had against posting it was the knee-jerk reaction some people will have towards presumed Apple fanboys preempting any consideration that an idea could be relevant. It might be worth giving that a thought.)


Cat on keyboard?


We also use Zzzz.


Pretty sure that a real 1940s Nazi would never use an Americanism such as Zzzz.

https://www.plushbeds.com/blogs/green-sleep/how-did-the-lett...


zzz command caused older versions of FreeBSD to go to sleep mode.


It's a joke


Save the jokes for Reddit


That's also a joke




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