Hacker News Reader

Comment by ary | Hacker News Reader

This is clearly not true. Having a second factor helps maintain security in the situation where your password is compromised (phishing is just one scenario). It isn't perfect, and can itself be defeated. However, compromising an account with 2FA is demonstrably more difficult than one without.

View on HN

While there are scenarios where 2FA can maintain security where a password is compromised, it's absolutely true that for a large swath of practical threat models, almost the entire benefit of 2FA comes in the form of assigning the shared secret instead of letting the user pick a weak and/or widely-reused password and the "having a second factor" bit doesn't really factor into the picture in any meaningful way.

These weaknesses are implementation specific. FIDO2/U2F is unphishable, requires proof of presence, and is a significant security win over a strong password.

Is PyPI requiring maintainers to use a hardware key? If not, I don’t understand how this policy is helpful.

Anyone who hadn’t already turned on 2FA is going to use the most frictionless so-called second factor they can.

They've been offering people hardware keys for free.

https://pypi.org/security-key-giveaway/

That's a great initiative, but I expect the maintainers who are interested to be the ones who've already turned on (some lesser form of) 2FA voluntarily.

Anyone who is turning on 2FA because of this requirement is going to select the most frictionless method of complying with the mandate. Which will not be a hardware key.

OK? So more people use TOTP and there's a marginal security win. And maybe a few use a token, and there's a significant win.

TOTP is a minuscule security win in exchange for a significant amount of inconvenience, versus using a good password manager. If you want to prevent password reuse, add an option to use a pre-generated password as an alternative to 2FA.

I think the statement "these weaknesses are implementation specific", while true, is irrelevant when 99% of people affected by this mandate (and 99.9% of 2FA users in general) are going to use an implementation with these weaknesses. And, I think it really sucks that PyPI is loosing maintainers due to a policy that won't increase security in a meaningful way.

The difference between a password manager and TOTP is that TOTP is something PyPI can enforce and a password manager is not.

Yes, TOTP adds very little advantage when you have an already safe password. But there is no way for PyPI to know if you're doing that or not, and they can know if you're using 2FA.

> 99% of people affected by this mandate (and 99.9% of 2FA users in general) are going to use an implementation with these weaknesses

Time will tell. PyPI is giving away free keys, presumably to encourage adoption of the safer option.

I'm actually very happy to see maintainers go. If they weren't willing to enable 2FA I worry about what other issues their software poses.

> Yes, TOTP adds very little advantage when you have an already safe password. But there is no way for PyPI to know if you're doing that or not.

But there is! Pre-generate a password for the user, instead of letting them supply one. This adds no extra inconvenience if you're already using a password manager, but it makes password reuse impossible.

So make a proposal for them to do that.

Okay, this is me proposing it! :)

I'm not the first person to come up with this idea. I think if PyPI had taken the approach of "here are our concerns, here is what we're protecting, here are some different options to make this work in the most convenient way possible", that would have been received very differently. Instead, they issued an ultimatum.

I think you'll find that in the course of making an actual formal proposal there are more caveats than you might imagine, and not necessarily as many upsides.

For example, just off the top of my head;

2FA as a general solution allows for U2F, which is significantly safer than your solution, even if it also allows for TOTP, which is "only" as safe as your solution.

It's also a change in user experience. Migrating users with existing passwords over to these new passwords may be more difficult for any number of reasons.

That's just a few seconds of thought. A real proposal might explicitly address these concerns. Like I said, feel free to make that proposal. A post on HN is not going to cut it, and it isn't going to help anyone. If you want to be more involved in how PyPI is maintained I suggest you do so.

I'm not calling it a weakness. I'm saying that the alleged advantages of the 2F in 2FA don't normally matter to people who just want to their shit to work.

If they can phish my password, they can trivially phish my OTP as well. The one thing I can see actually protecting against that is a physical hardware key, but that's a lot of extra inconvenience.

Reply on news.ycombinator.com