← Back to context

Comment by johnecheck

3 days ago

Sadly, touching the user-agent header more or less instantly makes you uniquely identifiable.

Browser fingerprinting works best against people with unique headers. There's probably millions of people using an untouched safari on iPhone. Once you touch your user-agent header, you're likely the only person in the world with that fingerprint.

If someone's out to uniquely identify your activity on the internet, your User-Agent string is going to be the least of your problems.

  • Not sure what you mean, as exactly this is happening currently on 99% of the web. Brought to you by: ads

    • If you're browsing with a browser, then there are 1000 ways to identify you. If you're browsing without a browser, then there is at least one way to identify you.

UA fingerprinting isn't a problem for me. As I said I only modify the UA for the handful of sites that use Anubis that I visit. I trust those sites enough that them fingerprinting me is unlikely, and won't be a problem even if they did.

If your headers are new every time then it is very difficult to figure out who is who.

  • yes, but it puts you in the incredibly small bucket of "users that has weird headers that don't mesh well", and makes using the rest of the (many) other fingerprinting techniques all the more accurate.

  • It's very easy to train a model to identify anomalies like that.

    • While it's definitely possible to train a model for that, 'very easy' is nonsense.

      Unless you've got some superintelligence hidden somewhere, you'd choose a neural net. To train, you need a large supply of LABELED data. Seems like a challenge to build that dataset; after all, we have no scalable method for classifying as of yet.

Yes, but you can take the bet, and win more often than not, that your adversary is most likely not tracking visitor probabilities if you can detect that they aren't using a major fingerprinting provider.

I wouldn’t think the intention is to s/Mozilla// but to select another well-known UA string.

  • The string I use in my extension is "anubis is crap". I took it from a different FF extension that had been posted in a /g/ thread about Anubis, which is where I got the idea from in the first place. I don't use other people's extensions if I can help it (because of the obvious risk), but I figured I'd use the same string in my own extension so as to be combined with users of that extension for the sake of user-agent statistics.

  • The UA will be compared to other data points such as screen resolution, fonts, plugins, etc. which means that you are definitely more identifiable if you change just the UA vs changing your entire browser or operating system.