[awesome_dude]

This is probably a naive question, but...

Doesn't the idea of swapping extension specific IDs to your browser specific extension IDs mean that instead of your browser being identifiable, you become identifiable?

I mean, it goes from "Oh they have X, Y , and Z installed" to "Oh, it's jim bob, only he has that unique set of IDs for extensions"

[triceratops]

It's not a naive question. This comment says it's not possible to do that: https://news.ycombinator.com/item?id=46905213

[awesome_dude]

Oh, it's (re)randomised upon each restart, whew, thanks for the heads up

edit: er, I think that that also suggests that I need to restart firefox more often...

[tech234a]

The webpage would have to scan the entire UUID space to create this fingerprint, which seems unlikely.

[throwaway808081]

Just have a database of UUIDs. Seems pretty trivial to generate and sort as it's only 16 bytes each.

[pshirshov]

That's actually a bright idea! Have you ever thought about applying for VC funds?

Once you deliver that, you can also think about a database of natural numbers!

[phanimahesh]

But that has no moat. Anyone can generate a database of natural numbers using SOTA models.

[stirfish]

lol

Let's go a step further and just iterate through them on the client. I plan on having this phone well past the heat death of the universe, so this is guaranteed to finish on my hardware.

  function* uuidIterator() {
   const bytes = new Uint8Array(16); 
   while (true) {
     yield formatUUID(bytes);

     let carry = 1;
     for (let i = 15; i >= 0 && carry; i--) {
       const sum = bytes[i] + carry;
       bytes[i] = sum & 0xff;
       carry = sum > 0xff ? 1 : 0;
     }
 
     if (carry) return;
   }
 }
 
 function formatUUID(b) {
   const hex = [...b].map(x => x.toString(16).padStart(2, "0"));
   return (
     hex.slice(0, 4).join("") + "-" +
     hex.slice(4, 6).join("") + "-" +
     hex.slice(6, 8).join("") + "-" +
     hex.slice(8, 10).join("") + "-" +
     hex.slice(10, 16).join("")
   );
 }

This is free. Feel free to use it in production.

[Velocifyer]

What license is this? Company policy says we can't use Apache licensed stuff.

[b00ty4breakfast]

Free space heater

[direwolf20]

It exists

https://everyuuid.com/

[fragmede]

The write-up for it is surprisingly interesting! https://eieio.games/blog/writing-down-every-uuid/#toc:entrop...

[xhcuvuvyc]

Woosh

[Mikhail_Edoshin]

16 bytes is a lot. 4 bytes are within reach, we can scan all of them quickly, but even 8 bytes are already too much.

Kolmogorov said that computers do not help with naturally hard tasks; they raise a limit compared to what we can fo manually, but above that limit the task stays as hard is it was.

[dullcrisp]

https://libraryofbabel.info/

[Dylan16807]

"Just" have a database, and then what? I can set up a database of all UUIDs very easily, but I don't think it's helpful.

[direwolf20]

Where are you storing them, a black hole?

[voussoir]

Relevant: https://news.ycombinator.com/item?id=42342382

[Ghoelian]

I don't think that's the case. I have the Earth View extension installed which shows a random google earth image.

I have this set as my homepage in Firefox as moz-extension://<extension-id>/index.html, and this has not changed since installing the extension. The page still works.

[jorvi]

Doing it on restart makes the mitigation de facto useless. How often do you have 10, 20, 30d (or even longer) desktop uptime these days? And no one is regularly restarting their core applications when their desktop is still up.

Enjoy the fingerprinting.

[tristan957]

I restart my browser basically every day.

[cyanydeez]

yeah I close out everything as a mental block against anything I'm working on.

I think there's a subset of people that offload memory to their browsers and that's kinda scary given how these fingerprint things work.

[Thiez]

There isn't enough energy in the solar system to count to 2^128. Now a uuid v4 number "only" has 2^122 bits of entropy. Regardless, you cannot realistically scan the uuid domain. It's not even a matter of Moore's law, it is a limitation of physics that will stand until computers are no longer made of matter.

[recury]

You just need to open so many instances and tabs in each instance that it crashes every couple days

[eek2121]

Umm, I restart my PC about once a week for security and driver updates.

If you don't, you have a lot more to worry about beyond fingerprinting...

Oh and I'm on LINUX (CachyOS) mind you.

[mrweasel]

Why does the browser even allow a website to query for installed extensions? I really don't see what the point of that would be.

The website should never be able to tell what's running in my browser, or on my computer in general. The browser renders the page, maybe runs a little Javascript, but there's no reason why it should be able to query anything about my environment.

I wonder how much stuff would break if the Chrome sandboxing was extended to preventing access to chrome-extension:// from Javascript loaded of random websites.

[b112]

Maybe, but how long are the extension ids? And if they are random, how long to scan a trillion random alphanumeric ids, to find matches?

I presume the extension knows when it wants to access resources of its own. But random javascript, doesn't.

[maples37]

The extension IDs are UUIDs/GUIDs, so 128 bits of entropy. No site is going to be able to successfully scan that full range.

[account42]

UUIDs are 128 bit long but generally have a bit less entropy than that as they are not just a random number. Still more than enough to make enumeration infeasible though.

[Sophira]

And just in case the magnitude of that isn't obvious to people, that means there are 340,282,366,920,938,463,463,374,607,431,768,211,456 total possible UUIDs. Good luck.

[b112]

ChatGPT told me it can be done though.

It won't disclose how, as it says it has had several users report it. And that it expects 50% of the bounty, and will use it for GPU upgrades.

[calvinmorrison]

yes thats how browser fingerprinting works and it is impossible to defeat because there are just too many variations in monitors (relevant for fonts), simple things like user agent, etc.

[ahoka]

And browsers trying to mitigate fingerprinting are miserable to use (fixed window size with only Arial available, etc) and probably fingerprintable anyway.