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Every V4 UUID

everyuuid.com

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Re: Every V4 UUID

#221

Post by MBCook »

savef wrote: post #186
zaken wrote: post #182

I tried to find the biggest UUID and if I got it right, it's 99999999-9999-4999-9999-999999999999 (note the 4 in the 3rd block) I'm curious why it's not 99999999-9999-9999-9999-999999999999 (all 9s)?

The values are hexidecimal, so all "9s" isn't the biggest UUID, but all "f's". Specifically, I think: `ffffffff-ffff-4fff-bfff-ffffffffffff`. The "4" in the 3rd block is the only permitted value as these UUIDs are using the GUIDv4 format. I'm not sure what's going on in the 4th block, but the references and linked RFC in the Wikipedia article might reveal more details: https://en.wikipedia.org/wiki/Universally_unique…

But if it’s all Fs, that means you have the sign bit set, so it’s not the largest.

It’s the smallest that’s less than zero right?

Re: Every V4 UUID

#223

Post by lelandfe »

ayaros wrote: post #189
mpeg wrote: post #2

Very useful! I'll refer to it when I forget my UUIDs, I use this site all the time to remember my bitcoin private key [0] [0]: https://privatekeys.pw/keys/bitcoin/1

See also: https://keys.lol/

I was going to "see also also" you with https://libraryofbabel.info/ but RIP for it is dead. https://en.wikipedia.org/wiki/The_Library_of_Babel_(website)

Re: Every V4 UUID

#224

Post by Dalewyn »

lxgr wrote: post #121
tobyjsullivan wrote: post #21

The fact that the search works impressed me more than anything. Of course, like every great magic trick, it seems so simple once it is explained. For the curious, here's the linked blog post describing how the project works: https://eieio.games/blog/writing-down-every-uuid/ Edit to add: I'd only tried searching for an exact UUID when I wrote this comment. I didn't realize it supports full text search! Now I'm even mo…

A great example of Teller's observation that "sometimes magic is just someone spending more time on something than anyone else might reasonably expect."

Sufficiently advanced technology is indistinguishable from magic, as the saying goes.

Re: Every V4 UUID

#225

Post by mckeed »

eieio wrote: post #157
cyanmagenta wrote: post #154

Earlier quoted context omitted.

It’s an interesting question whether that could be fixed. I think the answer is Yes. If the author didn’t do any scrambling, and just displayed UUIDs in numeric order, then it’s trivial to enumerate search results in order. Likewise, if you do something like adding a constant mod 16 to each hex digit, you could do the same thing when you generate UUIDs matching a substring. So the question becomes whether you could f…

FWIW I am super interested in this question but feel like I don't know how to derive a satisfying answer, maybe because the one of my goals here (add "enough" entropy) is a real fuzzy "I know it when I see it" sort of thing. But I'm gonna try to get a few more crypto-knowledgeable friends to chat with me about this and write up what I learn!

Would it be easier if only the lowest bits of the index contributed to the "entropy"? Like if the 2^16th UUID was the one right after the first and n + 2^16 was the one after the nth. You wouldn't notice the pattern but it'd be easier for the computer to handle. I guess if you were searching for a substring you might notice the ones surrounding the matches look almost the same from match to match...

Re: Every V4 UUID

#227

Post by kbhomes »

nomilk wrote: post #220
croes wrote: post #17

Seems like some hacker leaked all UUIDs. Check if your UUIDs are part of the leak.

I think this is a joke, but I think it is a problem if someone finds any sensitive uuid here, because the list on this website is a tiny subset of all possible uuids, so it provides a useful rainbow table for anyone attempting brute force attacks. I.e. generating and using random uuids would have an astronomically small success rate, whereas trying the ones on this site may not (depending on where they came from, whi…

You should check out the author's blog post about the site — it is quite literally every UUID, computed and rendered on demand.

https://eieio.games/blog/writing-down-every-uuid/

Re: Every V4 UUID

#230

Post by cubefox »

flkiwi wrote: post #216
cubefox wrote: post #205

Earlier quoted context omitted.

The most offensive sentence I could come up with leetspeak/hexspeak is this one: fe11a710-babe-4150-ace5-b19b1accd1cc (Yes it's a valid UUID) (I am so sorry)

Terrible day to be a very specific kind of literate.

What a horrible night to have a curse.
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