You're viewing a single thread.
I admit that passkeys have never made sense to me. You still have a username and password, but you’ve added a middleman who manages the password. Why not just use a password manager (without MFA, another useless annoyance)?
Passkeys are not passwords. When you authenticate using passkeys you will proof that you have the secret (passkey), but you will never reveal that secret to the service you are authentication against.
So even if someone is able to steal that package containing the answer, that answer will not be valid a second time.
So it’s like a credit card chip?
Its like the key in the Chip. But yes fundamentally it is like that. Now the Key needs to be stored somewhere safe like in your Phones secure enclave or in the case of your credit card a so called smart card (or sim card etc.)
I’m sorry, but this still sounds as much like “Mares eat oats” as it did when I first heard it a decade ago. You still enter a username and password somewhere (ideally in your password manager) to gain access to your account.
If you're entering a u/p along with a passkey, then it's MFA.
There are only a few sites I know of that do passkey correctly. CVS works wonderfully on my phone. Requires a username and then the passkey on my browser.
My company is working on a passkey only for login and it's really really slick.
You basically click "login" and then authenticate your passkey and you're in.
How do you authenticate your passkey?
Either with a pin or thumbprint
I must be dense. I just don’t see how that’s an improvement.
Admittedly my primary experience is with the code kiddies at my campus trying to implement Duo through a dozen redirects to Google, Microsoft, and whichever vendor platform we’re trying to login to. It’s a hot mess.
Your passkey is an encrypted message that authenticates you, the service you're trying to reach, and your computer.
If you go to a phishing site, the passkey won't even come up because the browser doesn't recognize the site. Granted a dumb user could still use their user/pass but ideally the user has MFA set up so they can't get far.
The goal of a passkey is to replace username and passwords entirely so that phishing becomes less common.
The main issue with passkeys is that unless you have something like a YubiKey or an authenticator (like bitwarden), the passkey is tied to the browser which means if the device gets lost you can't log in anymore.
I'm going to get technical. A registered passkey is basically your phone or whatever holding a private key and the server holding the public one. When you want to log in, you enter the username on the service, which contacts wherever you registered it, and asks for a verification. Then, the device creates a nonce, which is a random number to be used once (NumberONCE), and a copy of that number encrypted with the private key. Then, the service can unencrypt the piece and check that the value is the same as the unencrypted value. This process is called a digital signature, it's a way for online processes to verify the sender of whatever.
This way, the server knows that whoever is trying to authenticate is doing it from the authorised device. The difference between sending a signed nonce and a password, is that is someone steals the signed nonce they get nothing, since usually that number gets registered somewhere so it's not valid again or something, it's not exactly as explained but the point is that whatever is sent can't be sent again. Something like a timestamp in milliseconds where it will be obvious that the signature would have expired. If an attacker captures the authentication attempt, with passwords they get the actual password and can the use it again whenever, while with nonces, they can't.
Iirc, the server sends the device a code and the device must send the signed code back, so the service knows that the one trying to authenticate is the device. No need for passwords.
Now, if you need to authenticate to gain access to that private key, that's of course an attack vector, so if you want any kind of syncronisation of passkeys, you need to make sure that you don't need to send a password to get the pkeys. I use bitwarden, and unless I misunderstood, you don't authenticate against the bitwarden server, when you access your vault they actually give you you the encrypted data, which you then unencrypt with the password locally on the browser. I'll have to double checknon this because I have a 2fa on that for extra measure butidk how it actually works. My plan for the future is to actually use a yubikey to authenticate against bitwarden, following the same logic explained above, to then gain access to a bigger pool of passkeys. This way, ultimately all access is protected with my physical key which I can connect to most devices I use, and I can, with NFC use the key to authenticate the android bitwarden app, so it should be completely usable.
In any case, passkeys are better than passwords, provided toy don't store them in a less secure place. As we all know, the security level of a system is the security level of its weakest cog.
Thanks for this. For the first time, an explanation of passkeys makes sense.
It's one of the very few things Microsoft actually gets right on their websites. You select to log in with a passkey, authenticate, optionally select which account you want to use, and you're signed in. Not a single username or password entered into the website.
The difference is, that even if you enter the "password" on a phishing site, it is useless. Or when the server is compromised.
The only way the passkey can get compromised, is when the device that holds it gets compromised.
The same reason why hardware tokens for things like FIDO or U2F are recommended.
That makes no sense to me — and I’m not technically illiterate. If it makes no sense to someone like me, there was never any hope that it would be adopted by the masses who just want things to work. Google may not have helped here, and I’m certainly not among their fans, but it’s hardly entirely their fault that it never caught on.
The user does not need to understand it. A user does not understand https or hashing and salting. Still, every one of these is important these days for online security.
I am not a huge fan of passkeys themself, especially when the secrets are held by big tech, but they promise better security and protection against command n attacks like phishing.
I take your point. But I would argue that the user needs at least to understand the basic theory. Otherwise you get me, who sees no benefit, resents when it’s imposed unilaterally, and finds ways around the inconvenience.
You need to check out public key cryptography and digital signatures. Those are the basics of Fido.
When the private key is bound to a device it is not possible to fake or steal it through conventional methods. Passwords are the weakest link and an easy target for attackers - passkeys basically solve that.
User adoption depends on implementation, but everything is easier than remembering a secure password or using a password manager for most people. There needs to be an easy and secure way to distribute passkeys across devices, and any backup mechanisms may be a weak point. In any case: still better than passwords.
What makes no sense to you, exactly?
Users not having to remember a bunch of passwords makes a huge amount of sense to them. The support is already built into the devices they are using and it’s somehow, they don’t know or really care, more secure.
You have a point that it will be hard to explain this to everyone on why it is better.
From my understanding, when you use a password manager, the user will enter a pw into it that they remember and the vault will unlock. Then when they go to log into a website, a different, longer, and impossible to remember password will be sent to the site at login. (Assuming they are using the manager well). A week later when they go to log in again, the same long password will be delivered.
The problem is that if a bad actor gets involved, whether it is the website is attacked or they send the user a phishing url or something and the password from the manager is exposed, it will have to be changed. That scammer can now log into that website as the user whenever they want, and possibly any other website that user used the same password for. Hopefully they didn’t if they are using a manager.
With passkeys, a user will log into their manager with a password they remember, but when they go to log into a website, a different token will be sent, based on their key, every time. So if a scammer is listening at the router they still can’t log in again because it has expired.
It is still not a perfect thing, I would imagine that phishing sites could still get a scammer in, who could possibly do bad things or change the login credentials but it is still much more secure than sending a password to the site for the user.
Passkeys are. more similar to TOTP codes than passwords. Everything about passkeys is autogenerated. Browser negotiates with website to generate a key pair that will establish your identity on that site. Every time you "login" they exchange unique autogenerated keys to prove to each other who they are. That's it. You never have to remember anything again and it's impervious to many attacks that affect passwords and 2fa codes.
Where they fucked up is allowing big tech to call the shots so now instead of simply having passkeys in your browser you have to go to a higher authority to have them validated. And goes who that is — Google, Microsoft, Apple. So it's basically gatekeep and you can't touch them without depending on them.
How is that different from mutual TLS authentication?
Edit: It seems like OPAQUE just initiates mutual TLS authentication after the TLS session has already been negotiated with PKI. So it basically just allows websites to design their own login page instead of the one designed by the web browser.
It's like the initial authentication, where server and clientnexchange a symmetrical key with their asymmetrical keys. The difference is that in that exchange the server and the client meet for the first time whereas the point of pass keys is that once when you were already authenticated, you validated the device or whatever will hold the private key as a valid source, so then when the authentication code gets exchanged, both ends can verify that the other end is who they tell is, and both can verify the other end as valid, and thus that exchange authenticates you because you, in the past, while authenticated, trusted that device as valid.
Technically, yeah, it's an asymmetrical key exchange. Iirc the server sends you a signed certificate and you need to unencrypt itnwithbtheir public key and sign it with your private key, so they can the getnit back and ensure that it was you who signed it, using your public key to check the validity of whatever was sent.
I don't know enough to be 100% corrextbon the details, but the idea is that it's an interaction between asymmetrical keys.
Soporta like how we use keysbto authenticate through github through SSL, but with an extra level of security where the server validates a key in a single endpoint, not wherever that private key would be held (like with SSL)