No and stop using SMS it's not secure.
this post was submitted on 23 Sep 2023
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The least secure part of the sign-in process is the person. It doesn't matter what the 2FA method is.
You can be using a one time pin and someone can look at your paper and see the next one. Someone can trick your grandma into giving out the Google authenticator pin over the phone because "they're from Google". Someone can trick you into making the financial transfer yourself because "you're getting a deal".
Sim swapping
Which is why sms-based 2fa is useless if you're being targeted by a motivated hacker. If you're an important person (e.g. a government official, an exec on a big corp, a celebrity, etc) it's not safe to use sms-based 2fa. Heck, even if you're nobody, a hacker might decided to target you anyway to access the company you're currently working at, or because you have something they want (e.g. a desirable Twitter handle). One call to your cellphone carrier to complain about losing phone, with some social engineering skill to dupe the minimum wage call center worker who doesn't really care about being vigilant, and suddenly the hacker gain access to your cellphone number (doubly easier to with e-sim) and thus your sms-based 2fa.
TOTP or hardware based tokens ftw
On some websites, it is the only option.
Although it's true that you are increasing the attack surface when compared to locally stored OTP keys, in the context of OTPs, it doesn't matter. It still is doing it's job as the second factor of authentication. The password is something you know, and the OTP is something you have (your phone/SIM card).
I would argue it is much worse what 1Password and Bitwarden (and maybe others?) allows the users to do. Which is to have the both the password and the OTP generator inside the same vault. For all intents and purposes this becomes a single factor as both are now something you know (the password to your vault).
That’s not quite right though, there’s the factor you know (password to your vault), and the factor you have (a copy of the encrypted vault).
Admittedly, I don’t use that feature either, but, it’s not as bad as it seems at first glance.
That’s not quite right though, there’s the factor you know (password to your vault), and the factor you have (a copy of the encrypted vault).
That would be true for offline vaults, but for services hosted on internet I don't think so. Assuming the victim does not use 2FA on their Bitwarden account, all an attacker needs is the victim's credentials (email and password). Once you present the factor you know, the vault is automatically downloaded from their services.
This is something I hadn't thought until know, but I guess password managers might(?) change the factor type from something you know (the password in your head) to something you have (the vault). At which point, if you have 2FA enabled on other services, you are authenticating with 2 things you have, the vault and your phone.
Assuming the victim does not use 2FA on their Bitwarden account
A pretty tall assumption given that we're already talking about someone who knows to turn on 2FA for other things. If someone knows about 2FA and password managers, they'd be insane not to have 2FA set up on the password manager itself.
That's a fair point. I just wanted to highlight that there may be cases where a password manager isn't automatically protected by 2FA by the two factors you mentioned (The password you know and the copy of the vault) since in the case of bitwarden fulfilling one can give you the second. In order to actually achieve 2FA in this case, you would need to enable OTPs.
Certainly fair.
And yeah, I personally use Bitwarden with 2FA on the Bitwarden account, but don't store any 2FA tokens in Bitwarden, handling them all separately. Don't want all the eggs in one basket.
Though given I have fingerprint access on phone and computer for bitwarden, i suppose that one basket is my finger. But if someone is taking my finger, I've got more immediate concerns than my passwords.
It works for self hosted vaultwarden mostly also. Since you would need a way to acess the login page itself, which could be behind a VPN or other authentication service like Authentik.
Many password managers use a biometric factor to sign in (your fingerprint, for example, using some kind of auth app if needed). This basically moves the MFA aspect to one service (your password manager) instead of having each service do their own thing. It also comes with the benefits of password managers - each password can be unique, high entropy, and locked behind MFA.
Many password managers use a biometric factor to sign in
The only thing this does is replace the authentication mechanism used to unlock the vault, instead of using your master password (something you know), it uses some biometric factor (something you are), although it uses your biometric data, it's still a single factor of authentication
This basically moves the MFA aspect to one service (your password manager) instead of having each service do their own thing
I am not sure I understood you here. What do you mean by "instead of having each service do their own thing"? Each website using their own method of delivering OTPs?
It also comes with the benefits of password managers - each password can be unique, high entropy, and locked behind MFA.
I am not discrediting password managers, they have their uses, as you mention you can have unique, high entropy password on a per service basis. The only thing I am against is the password managers themselves also doubling as OTPs generators (take a look at Bitwarden Authenticator which kinda defeats the purpose of OTPs. From the perspective of OTPs it makes much more sense to use a separate application (Like Google Authenticator or Aegis Authenticator), preferably on a separate device, to generate the OTPs.
although it uses your biometric data, it's still a single factor of authentication
Speaking from my experience, I use my phone for biometric authentication. At least from my point of view, I see that as two factors (what I have and what I am) since the biometric authentication only works on my phone.
I am not sure I understood you here. What do you mean by "instead of having each service do their own thing"? Each website using their own method of delivering OTPs?
Basically having multiple places where codes may be generated. This way you can use one location to get OTPs instead of having them delivered via SMS or generated by a different app/service. It ends up being easier and more convenient for the end user (which of course increases adoption).
I guess this has more to do with services adopting OTP generators than sending them via SMS though.
From the perspective of OTPs it makes much more sense to use a separate application (Like Google Authenticator or Aegis Authenticator), preferably on a separate device, to generate the OTPs.
If logging into the password manager to get the password is sufficiently secure (locked behind MFA), then I don't see the benefit of using a separate OTP generator (aside from maybe if your password manager has a data breach or something, which should be a non-issue except it clearly isn't thanks to LastPass...)
I'm starting to wonder if phones (or other auth-specific devices) should just become dedicated authentication devices and passwords should just be phased out entirely tbh. Passwords have always had issues because their static nature means if someone learns your password without your knowledge, that method of authentication becomes worthless. The main concern would be what happens when you lose your phone I suppose.
This is why we require second factor on the password manager too, otherwise you’re exactly right.
USPS’ website does this, sort of.
If their text service is down it’ll let you know and just skip the 2FA process even though normally they offer an option to get the code via email.
The fact that they do this is bad enough, the fact that this happens so often that I’ve seen this at least a dozen times is even worse.
I appreciate the quick hack, but with a little more foresight you could have just put up a blurry jpeg with that number and changed the prompt so it looks like a CAPTCHA. Nobody would have given it a second thought.