**Biometric Apps Will Soon Be Pushed Across the Web**
This is a bad idea:
1. You can't "reset" your biometrics like a password.
2. Biometrics aren't hashable. The end result is they're less secure than other forms of authentication. (If you don't understand what this means, you're not qualified to have an opinion on this matter.)
3. You can't control what happens to your biometrics once they're in the hands of a 3rd party.
Please re-Toot.
@profoundlynerdy Wow, I feel dumb for that not thinking about that that they're easily retrievable already lol. But thanks!
You could at least say the attacker has to be able to be near anywhere you frequent to be able to get the prints at least. I don't think they'd have value on shady markets just yet since biometrics aren't thaaat widespread.
@profoundlynerdy Agree. Biometrics can never be more than an additional check on identity, leaving the need for secure authentication still having to be meet.
@profoundlynerdy In a world of 7bn, there are people who more or less share your face. Do not want.
@profoundlynerdy SO Disney World required my finger scan, to get in the park...and the supervisor I demanded to speak with, couldn't understand why I didn't want them to have it, or retain it. But my kids wanted to go...so I went along thinking all the things you just mentioned. :(
@digasi Yeah, that sucks.
Disney has changed a lot, I'm sure. I haven't been to Disney Land since Reagan. I feel old.
@profoundlynerdy Maybe I'm tripping, but why can't you salt, pepper, and hash a biometric authentication?
I'm unclear on what the reference to SHA256 is here: https://www.w3.org/TR/webauthn/#sctn-uvi-extension
Can you help me understand?
@christianbundy Absolutely. Fair question.
In a nutshell it's because no two scans of your biometrics are digitally identical. Scan your finger print a thousand times and you'll have that many slight variations from scan to scan that are within some epsilon of a "perfect" scan.
More details here:
https://hackaday.com/2015/11/10/your-unhashable-fingerprints-secure-nothing/
Enjoy the read.
@profoundlynerdy Thanks! I haven't read the article yet (starting now), but I wonder whether you could delegate biometric authentication to a TPM and/or 2FA hardware.
I suppose that's basically what we're already doing with mobile biometrics anyway? Time to read!
@profoundlynerdy
why are they not hashable? it's not like you're actually storing someone's fingerprints; they're just data points, can't those be encrypted too?
@profoundlynerdy I did post this before reading the other responses.
So, I'll add to the question. As someone pointed out above, wouldn't the best case be that biometrics unlock a password manager, where the passwords are hashed?
@warburtonstoryaddict The problem is it's not as hard as it sounds to spoof your biometrics.
I've shared this a few times. Let me know if it's duplicate from your perspective: https://hackaday.com/2015/11/10/your-unhashable-fingerprints-secure-nothing/
@profoundlynerdy this was helpful, thanks!
So since it looks like biometrics are here to stay, if people insist on using them they really should be for real-time, two step verification and nothing else?
@warburtonstoryaddict I'm not even sure that works.
@profoundlynerdy Great, soon we'll need to use our devices with prosthetic finger prints. Then we can revoke and change them. And it will all be in the name of "convenience".
@profoundlynerdy @cedric Would they be using raw biometric data? I would think it'd make more sense to do something like soft-u2f unlocked locally by fingerprint, but only the challenge-response is sent across the web. Raw biometric is bad both from security and efficiency standpoints
@profoundlynerdy I think you're misunderstanding how biometrics work in this application. Biometric data isn't sent over the network; it's used to unlock a secret stored in a local secure vault. Along with retry limits it's just a thin layer of security on top of the need to possess the device. Almost certainly more secure than a password and definitely more convenient.
@profoundlynerdy And also police can't force you to tell them password, but they can force you to touch the device and unlock it.
@profoundlynerdy well you can hash it but that kinda pointless
@profoundlynerdy heh heh hands of a third party
@profoundlynerdy 2. is not entirely true - there are "biometric hashes" that provide some of the same one-way properties as conventional crypto hashes. The amount of security when you need to be able to do a fuzzy match is somewhat limited, though.
@profoundlynerdy Some explanation about 2. Biometrics aren't hashable.
https://hackaday.com/2015/11/10/your-unhashable-fingerprints-secure-nothing/
@profoundlynerdy Biometrics *are* hashable -- any data is. What was possibly meant is that biometric hashes are too susceptible to collision, either accidental (resulting in misidentification) or voluntary (resulting in usurpation).
(had the "not hashable" statement not been "backed" by a argument of authority, I would have remained silent. Next time, don"'t deny others their opinions, and especially don't deny them that because "I know and you don't".)
@profoundlynerdy I'm still a fair bit of a noob in the whole security sphere, so I'm wondering why exactly they aren't hashable? Aren't they already decoded into a (uniquely) identifiable string or something, which can then be hashed like a password?