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Emailing a one-time code is worse than passwords

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Re: Emailing a one-time code is worse than passwords

#212
post #3

I thought this was going to be about Passkeys. Maybe if the FIDO Alliance can stop being obstinant and allow real backups, I'd be all in on them.

But if you could back up a passkey, wouldn't the key just be a password? (I do agree with you about backups being essential, but my conclusion was "the idea is fundamentally flawed," rather than "it's one tweak away from greatness.")

No, because unlike a password you never provide the private key for a passkey to the site you’re logging into, which is how many password breaches occur.

Re: Emailing a one-time code is worse than passwords

#213

The attack pattern is: 1) User goes to BAD website and signs up. 2) BAD website says “We’ve sent you an email, please enter the 6-digit code! The email will come from GOOD, as they are our sign-in partner.” 3) BAD’s bots start a “Sign in with email one-time code” flow on the GOOD website using the user’s email. 4) GOOD sends a one-time login code email to the user’s email address. 5) The user is very likely to trust…

> “Click a link in the email” is a tiny bit better because it takes the user straight to the GOOD website, and passing that link to BAD is more tedious and therefore more suspicious. "Click a link in the email" is really bad because it's very difficult to know the mail and the link in it are legitimate. Trusting links in emails opens to door to phishing attacks.

Yeah, I was frowning when I read that. It is not any better at all, not even a tiny bit.

Re: Emailing a one-time code is worse than passwords

#214
And there is _NOTHING_ worse than being locked out of an account because without asking they reverse the password and second factor authentication while your traveling and don't have access to a phone/etc.

Nevermind. that pretty much all services treat the second factor as more secure than my 20 character random password saved in a local password safe. And those second factors are, lets see, plain text over SMS, plain text over the internet to an email address, etc, etc, etc.

Re: Emailing a one-time code is worse than passwords

#215
post #108

Earlier quoted context omitted.

The attacker would just ask you for the TOTP code and forward that to Google.

In practice it's maybe slightly harder, because they'd have to convince a user to enter their google 2fa code into a site that isn't obviously google? I'd imagine a convincing enough modal would do the trick though, in a lot of cases.

If we are talking about TOTP, there is a time limit to that, which makes it harder, yeah.

Re: Emailing a one-time code is worse than passwords

#216

I read this sentence 4 times and I still can't parse it: > An attacker can simply send your email address to a legitimate service, and prompt for a 6-digit code. You can't know for sure if the code is supposed to be entered in the right place.

Because the sentence makes no sense, but what the author wanted to say was:

- You are in front of the attacker site that looks like a legitimate site where you have an account (you arrived there in any way: Whatsapp link, SMS, email, whatever). Probably the address bar of your browser shows something like microsoft.minecraft-softwareupdate.com or something alike, but the random user can't tell it's fake. The page asks you to login (in order to steal your account).

- You enter the email address to login. They enter your email address in the legitimate site where you actually have an account.

- Legitimate site (for example Microsoft) sends you an email with a six digit code, you read the code, it looks legit (it is legit) and you enter it in the attacker site. They can now login with your account.

Re: Emailing a one-time code is worse than passwords

#217
post #189

Earlier quoted context omitted.

I don't understand your example. > 2) BAD website says “We’ve sent you an email, please enter the 6-digit code! The email will come from GOOD, as they are our sign-in partner.” Does that mean that GOOD must be a 3rd party identity provider like Facebook, Apple, Google etc?

There are sites that send you immediately a 6 digit code just by entering your email on their sign in page, they don’t even request a password. That means you could be phished on a fake website that when you enter your email there they do it on the real site, then you receive the real good code and enter it on the fake site.

It is just the same old stuff with username & password combination. I used to duplicate websites, they looked exactly like the original, except I was storing the entered username and password combination. I did this when I was a kid. The process is the same (or very similar) with everything else that is not a password.

Re: Emailing a one-time code is worse than passwords

#218

The attack pattern is: 1) User goes to BAD website and signs up. 2) BAD website says “We’ve sent you an email, please enter the 6-digit code! The email will come from GOOD, as they are our sign-in partner.” 3) BAD’s bots start a “Sign in with email one-time code” flow on the GOOD website using the user’s email. 4) GOOD sends a one-time login code email to the user’s email address. 5) The user is very likely to trust…

The scheme is impossible, because the GOOD site says in the email "NEVER SHARE THIS ONE TIME CODE WITH 3RD PARTY APPS OR INDIVIDUALS"

Re: Emailing a one-time code is worse than passwords

#219

The attack pattern is: 1) User goes to BAD website and signs up. 2) BAD website says “We’ve sent you an email, please enter the 6-digit code! The email will come from GOOD, as they are our sign-in partner.” 3) BAD’s bots start a “Sign in with email one-time code” flow on the GOOD website using the user’s email. 4) GOOD sends a one-time login code email to the user’s email address. 5) The user is very likely to trust…

> “Click a link in the email” is a tiny bit better because it takes the user straight to the GOOD website, and passing that link to BAD is more tedious and therefore more suspicious. "Click a link in the email" is really bad because it's very difficult to know the mail and the link in it are legitimate. Trusting links in emails opens to door to phishing attacks.

I know not to click links on random emails but comfortably click links on emails I initiated from a website.

Re: Emailing a one-time code is worse than passwords

#220
post #170

Earlier quoted context omitted.

If you like password managers, you'll love passkeys! Passkeys is an interface between your password manager and a website without all the fluff with filling or copy-pasting passwords.

No need to write like that. I know, understand and use passkeys for quite a while now. I don't love them. I don't love passwords either. But while I don't fear passwords, I fear passkeys. The reason is that it makes the tech even more intransparent. My password manager stops working, completely dies or I can't use it anymore for other reason? No problem, I can fallback to a paper list of passwords if I really have to…

What about server-generated passwords, like API keys? That would solve the main problem with passwords, namely, that people reuse the same weak password everywhere. I doubt it would be as popular as user-selected passwords, but I still wonder why no website has tried it.
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