3
votes
1answer
53 views

How secure are the FIDO U2F tokens

Google and Yubico just announced the availability of cryptographic security tokens following the FIDO U2F specification. Is this just another 2FA option, or is this significantly better than solutions ...
-1
votes
1answer
25 views

Can OTP 2FA be reversibly determined?

Please note: I'm not necessarily talking about what happens when one shoulder surfs someone inputting a OTP. I'm fairly confident that it's nearly impossible (or extremely impractical) to guess the ...
0
votes
2answers
71 views

Are there any flaws in my design for a paper-based OTP grid?

I'm trying to implement two-factor authentication on the cheap for a website of mine. My bank uses this sort of grid-based OTP system, so I wanted to emulate it in my application: Cards are ...
9
votes
2answers
700 views

LastPass Grid Authentication vs Google Authenticator which one is more secure?

[Being a LastPass user] recently I moved to Google Authenticator instead of using Grid Authentication as a 2-factor security. For me, finding and filling letters from such a dense matrix is a rather ...
1
vote
0answers
37 views

Is there a TOTP variant that does not require the user to type in a code? [closed]

We're considering a 2 factor TOTP solution on a mobile phone. However, it would be much easier for the user to somehow send the OTP to the server by pushing a button, rather than manually typing in a ...
2
votes
2answers
66 views

HOTP/similar - how about standard backups of mobile devices?

I was considering adding HOTP as an option to my website (alongside things such as SMSed one time tokens which I already have). But I was considering one issue that HOTP inherently has: Things such ...
4
votes
2answers
531 views

Is OATH TOTP and / or Google Authenticator vulnerable if an attacker has (N) previous codes?

I'm not much of a ipsec initiate, so this is a bit over my head ... but I'm always willing to learn more. Are there any known attacks against OATH TOTP (Google Authenticator's / Authy's algorithm) if ...
5
votes
2answers
3k views

Does adding two-factor authentication by OTP really make KeePass more secure

KeePass is an application that keeps all your passwords for you in a database. It is primarily protected by a master password and/or keyfile. If the database is properly encrypted with that password ...
10
votes
4answers
676 views

What is the use of the “secret” displayed when setting up 2 Factor Authentication?

What is the purpose of the "secret" that is displayed when you take the picture of the QR code to set up 2 Factor Authentication on a non-Google site? Why would you need it? If you save it, doesn't ...
1
vote
1answer
363 views

What is more secure for voice and SMS OTP: A random number or generated similar to HOTP?

Many providers are creating OTP authentication for their sign in. However I noticed that all the voice and SMS OTPs I've come across are a series of 6 digits... similar to the HOTP RFC Standard ...
10
votes
3answers
1k views

What is the risk and mitigation of accidentally typing a YubiKey password in an open forum?

I have a YubiKey in my laptop (for testing) and accidentally broadcast my YubiKey password out to the Internet. Since this is only a test key, and has no access to anything of value, here are some ...
2
votes
1answer
511 views

Is Dual Factor possible during boot with whole disk encryption on Mac FileVault 2

Mac FileVault 2 is the default disk encryption for newer Macs that occurs in the EFI pre-boot phase. The challenge here is that most smartcard drivers are loaded after the OS loads. Is anyone aware ...
4
votes
4answers
713 views

SMS Authentication: random OTP or a cryptographic one

I'm adding two-factor authentication using SMS to enhance an existing login process. Since I'm not working with physical tokens, I was wondering what is considered the safest: Sending random 8 ...