FIDO (Fast IDentity Online) is a technical specification for biometric authentication to online services.
Questions tagged [fido]
62 questions
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Where are FIDO U2F Keys Stored?
I'm getting conflicting information on how the security keys are stored and used. Where are the public and private keys stored? If the private key is stored on the Yubikey itself, how many can it hold?
If the both keys are stored on the service you…
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Derpy
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How does the attestation mechanism of U2F guarantee the provenance of the key material?
I'm trying to understand Yubico's documentation of the U2F standard, and getting hung up on the PIV attestation piece.
The security claim appears to be that the authoritatively-signed attestation certificate sent by the device upon registration will…
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Dan Lenski
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How should I implement FIDO UAF architecture?
I'm new to FIDO (Fast IDentity Online), and want to add FIDO UAF (Universal Authentication Framework) support to my website. I've few queries:
Suppose, I've built my own FIDO Client. Is there any test server where I can test my FIDO Client, or do I…
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anonImos
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Using Fido U2F or similar as primary authentication method?
I've been wondering about this for a while, but couldn't find much on the web, so I hope that someone could point me in the right direction for better understanding about this topic.
Would it be viable / safe to use something like a Fido U2F device…
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redShadow
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Benefit of using OpenSSH FIDO/U2F support over GPG mode?
OpenSSH version 8.2 introduced support for FIDO/U2F hardware authenticators, via the new public key types "ecdsa-sk" and "ed25519-sk".
I currently have SSH authentication set up in combination with gpg subkeys by using my security key in GPG mode. I…
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nyronium
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password managers and FIDO
I've just been reading some posts about FIDO support (or the lack thereof) in password managers and want to check whether my understanding is correct.
My understanding of FIDO (v1) is that the device contains a secret that it will never let out of…
user16214
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U2F FIDO sends identifiable serial numbers
As all of the FIDO Alliance documents state, the FIDO U2F protocols should never be able to abused to identify whether a user has multiple accounts with one service, or for services to collude and find out a specific user's identity.
So why, when I…
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Ed Watson
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Is FIDO2 authentication vulnerable to a social engineering replay attack?
I'm starting to learn about the FIDO2 standard, and I'm wondering if this scenario is possible...
Victim visits a credential harvesting page and enters their credentials
Credential harvesting backend opens a connection to the legitimate login page…
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Sean W.
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How does ed25519-sk actually works?
My google-foo failed me as most "how it works" sections related to fido are very... let's say... consumer-oriented.
So openssh supports U2F natively when using the appropriate elliptic-curve-based cipher (namely ed25519-sk and the NIST one, do mind…
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Jane
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FIDO U2F - MacOS TouchBar
I understand how FIDO works with yubikey: Yubikey device has a symmetric key and it uses appId, nonce and symmetric key to generate key pair for a website. And the device gives back public key and keyHandle (which can used to generate private key)…
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Jack
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How do FIDO keys prevent MITM reflection attacks?
FIDO keys, used for 2 factor authentication are based on a challenge-response mechanism.
Besides generating a common 1-time-key using diffie-hellman, or transferring all data over TLS, how can they prevent reflection attacks?
Challenge: Alice -> Eve…
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Bharel
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U2F protocol - Counter value & device cloning
My question is about the U2F protocol and more precisely cloning detection.
According to the doc :
"If there is a possibility that a U2F token can be cloned, we also need some way to detect it. We can do this by having an operation counter. Every…
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QBl
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In the context of FIDO U2F, when is a new ephemeral key reused, or cached?
I'm reading this paper from Yubico on Universal Second Factor
and OpenID Connect and see the description about ephemeral keys
I'm confused on when a ephemeral key is used, and under what conditions they are cached.
From the Yubico document.
Page…
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makerofthings7
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Vulnerabilities despite FIDO U2F?
FIDO U2F seems much more secure than one-time-passwords (OTP), especially TOTP, because of the challenge-response architecture. In what ways is a U2F user still vulnerable?
I presume if a user's computer is compromised or the user loses their U2F…
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Jeff
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Why would a U2F key be more secured than an OTP device?
I have a Yubikey 5, I can store a PGP key inside, it has OTP abilities, FIDO, NFC, etc... Which is great for a device like this.
First of all, I understand how a smart card is more secured than an app/sms based OTP for instance, but seeing how the…
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Max13
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