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25

Let's check out what PGP and SSH actually offer for this purpose: PGP: Client must install PGP software which is not installed by default in the majority of the systems. Client must create a PGP key pair. Then he must send the public key to the server so that the server can use it later for validation. When authenticating with 2FA the server will send a ...


24

Here www.dongleauth.info is list of websites, self-hosted software and USB dongles compatible to U2F (as well as One Time Passwords)


13

"Phishing" is a broad term for online social engineering attacks where the attacker impersonates somebody the victim trusts. Phishing attacks can have many goals; basically anything that the the user could be persuaded to do on behalf of the impersonated entity. 2FA protects against certain attacks, and some forms of 2FA provide better protection than others,...


10

From a technical point of view, your question totally makes sense. U2F and UAF were pushed by very different actors/players. UAF was backed (cough plagued cough) by biometrics companies and never took off for many reasons. U2F is a simpler no-nonsense solution that is now largely adopted by major web services providers like Facebook, Google services (...


10

Lack of portability SSH and PGP are widely used, but they are not web technologies. There has been an equivalent web technology for many years - SSL client certificates. However, this is not much used. The reason is the lack of portability. If you have an SSL client certificate on your home desktop, it's difficult to move it somewhere else. So you can't ...


10

[This is my view, I'm not claiming that it represents the view of the industry] I totally agree that some piece of secret data stored on your main device blurs the line between "something you know" and "something you have". Which side of the line it falls on, I think, depends on the specifics of what that data is and how the authentication protocol works, ...


8

No, you are safe Even if you entered it inside a malicious computer, your key could not be compromised. It uses the same security as a credit card; meaning a smart card. This smart card contains a private key that is not disclosed unless you physically open the smart card. This is the reason why credit cards with a smart card are so much better than credit ...


6

Standard password (even locally encrypted), xOTP (OTP, HOTP, TOTP) [with or without SMS codes] have many vulnerabilities and the most important now is : NO REAL PROTECTION AGAINST PHISHING. A quick visual reminder about that : http://www.neowave.fr/pleaseno/SMS_OTP_TOTP_QRCODE_SSL_ARE_NOT_SOLUTIONS.pdf FIDO U2F is a true but simple PKI based solution (...


6

In my opinion U2F lacks one thing at the moment: The privacy of your secret key. Each device comes with it's own secret key. A site specific key is derived from this secret key to do the challenge response when logging in to a site. This is ment to keep you anonymous and easily register and authenticate at a site. But! Each U2F device that is sold nowadays ...


6

Here's the issue with U2F as being the only method of authentication: there is no verification that you are the rightful owner of the U2F device just because you have it in your possession. If U2F was the only form of authentication for everything, that would be like having one master key for your car, house, safe, safety deposit box, office door/building, ...


5

Assuming your device supports the generation and use of multiple keys, identifying information is not shared across services by the use of U2F. You will likely find the following comment from Yubico to be interesting: Each user can also choose to have multiple identities, including anonymous (no personal information associated with the identity). A U2F ...


5

No, the U2F specified keys are not able to perform symmetric encryption operations. They are designed only for providing a public key, attestation certificate, and signing data for the challenge / response process with their internal private key. Specifications can be read at https://fidoalliance.org/specifications/overview/


5

I think the point of the saying "if attackers own your machine then you are already screwed" is showcased with your question. You don't want your password manager to decrypt anything except the single password you're requesting. But any malware on your system can intercept and change that request. This theoretical malware can tell your password manager to ...


5

In short, UAF will have a role as a single factor authentication. That is mainly achieved by biometrics in order to replace passwords, to replace "what you know" with "who you are," in addition to some crypto techniques like PKI. U2F still has a role as a second-factor ("what you have") in addition to username/password ("what you know"). This property ...


5

No, and they are not saying that they can prevent the phishing of passwords. They are saying that phishing the password alone will not give the attacker access to your account. You can enter your Gmail password in your question above and U2F will not prevent that. In the same way, a phishing site can gather credentials and U2F is not involved at any point. ...


5

If you're not using TLS, FIDO keys (WebAuthn or U2F) aren't going to do you much good. In fact, the spec requires that browsers only expose the API in secure contexts: The client facilitates these security measures by providing the Relying Party's origin and RP ID to the authenticator for each operation. Since this is an integral part of the WebAuthn ...


5

When you setup a new hardware token, you're usually presented with one of two options: you can either let the token generate a new key or you can program it with a key you generated outside the token. By design, keys that are stored by a 2FA token cannot be read out of the token. That doesn't mean that in the future, someone can't find a vulnerability in ...


5

Username and password alone or together with WebAuthn1 only offer an authentication of the user. Modern authentication methods used by the banks like PhotoTAN instead authenticate each transaction separately: not only it gets checked that the user is present but the transaction information are displayed on an independent system (app on mobile phone or ...


5

The keys can be either stored on the device, or encrypted and returned in the key handle. Both are allowed (and mentioned) by the spec. From the implementation considerations: U2F tokens might not store private key material, and instead might export a wrapped private key as part of the key handle. Also in the raw message format specification: A key handle ...


4

The Yubikey Neo can do all three things you need. The standard Yubikey (non NFC) is, according to the website, in the process of beeing FIPS 140-2 certified. An overview of certified U2F tokens can be found on the fidoalliance website Generally speaking, U2F is a rather new standard, and the mainstream crypto token producers like Gemalto or SafeNet haven't ...


4

lots of confusion here... but that's normal :) Reminder: Each time a user enrolls a FIDO U2F device (FIDO U2F USB security key, FIDO U2F NFC card, FIDO U2F BLE device), a new key pair is needed and created. Inside FIDO U2F Specifications, there is a section called "7. Allowing for Inexpensive U2F Devices" (http://gg.gg/4eny2) describing how a manufacturer ...


4

Because additional auth factors should, ideally, be out of band. Like a phone, or token, or some kind of telepathic message. U2F is good because you CAN'T extract the private key and it requires a physical touch to the device before it will sign.


4

The YubiKey NEO is a unique One-Time Authentication device which combines the functionality of a YubiKey Hardware Authentication device with the extended capabilities of a smart card, without requiring additional drivers or software. The YubiKey NEO has 3 major elements - the first is the YubiKey element, which allows the YubiKey to be used as a ...


4

As far as I understand it (with help from agl's blog post): security.webauth.u2f controls the original FIDO U2F API introduced by Chrome. security.webauth.webauthn controls the now-standard W3C WebAuthentication API. They both let you talk to existing U2F (CTAP1) devices, but using different JavaScript functions. Webpages written for Chrome's "extension" ...


4

No, this is not possible. Secrets can't be extracted from Yubikey tokens once they've been written. U2F keys don't even allow the secret to be written.


4

If the transport security between the User Agent and the Authenticator is broken there are some (debatably minor) issues: The AppID is disclosed when you log into a site (this is usually the domain of the site) If the attacker is nearby and knows your password he might be able to submit the token's signature of the website's challenge before you (depending ...


4

Does it mean MAC OS implemented U2F protocol? No, it means that Chrome implements U2F by using properties of the TouchBar. From Issue 678128: Use TouchBar/TouchID as a secure element for implementing a U2F security key: ... The new MacBook Pros with TouchID have a secure enclave for storing the fingerprint data. We may be able to use this element for ...


3

If someone steals my U2F, they get unfettered access to every site that uses it as a single factor, until I manage to remember every site I've used it and revoke it from all of them. The level of effort to steal a U2F device out of my USB slot is orders of magnitude less than to steal the database for my password manager plus the password to unlock it. And ...


3

I presume if a user's computer is compromised or the user loses their U2F dongle then all bets are off, right? But phishing no longer works? The documentation I'm making statements in regards to this comes from the Protocol Design + User Flows document at https://sites.google.com/site/oauthgoog/gnubby Malware on a machine can generate fake origin messages ...


3

I am pretty sure there is no correct answer to this and similar to Mikes post this is only my view… The main weakness with using phones is the propensity for a reliance on SMS messages to demonstrate access to the device. While not trivial, it is possible to clone a SIM without physical access to the device or SIM, and places a reliance on procedures out ...


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