[Sir_Cmpwn]

They don't support realying their user's outgoing mail through SMTP. They have to support server-to-server SMTP to receive incoming mail. The latter is where they encrypt incoming emails, but they could just as easily store the plaintext and you'd never know.

[gruez]

that limits it to the moment the email was received, which is still better than everyone else, where you can read the mail any time in the future.

[Sir_Cmpwn]

Not if they store the unencrypted email when it was received without telling you. Then they could refer to their stored, plaintext copy of the email at any time in the future.

[mynameisvlad]

When they claim to provide secure email, what benefit do they gain from lying to all their users and potentially being discovered and the blowback from that?

It's great that you aren't taking things at straight face value, but they have very little benefit from doing what you say they could hypothetically do and an incredibly amount of risk and potential to blow up in their faces. In business terms, it's a ludicrous proposition to actually do what you claim they could do.

At the end of the day, you can claim all the hypotheticals in the world, but do you have any proof that they're actually doing anything remotely like what you say they could be? Because I haven't seen anything that would come even close to the scenarios in your hypotheticals.

[Sir_Cmpwn]

What happens when their government compells them to secretly begin siphoning off email, ala Lavabit?

[mynameisvlad]

Once again, massive hypothetical. Is there any proof this is even remotely the case? Has Switzerland's government suddenly decided centuries of consumer privacy go out the window and are asking to do such a thing or even implying they would? Yes, it's possible, but, once again, there's absolutely no indication that this is even remotely going to happen. At a certain point, hypotheticals like this just plain aren't helpful.

You claim they're "a scam". That has certain implications, including willful misuse of data/money. Can you prove they're actually "a scam", or is all of this just posturing because they aren't running their company in the exact way you would want them to?

[Sir_Cmpwn]

Why do we have to engage in hypotheticals about whether or not anyone will act in a morally upstanding way when we could instead design systems which don't require trust at all? Or better yet, use estalbished systems which don't require trust?

[Dylan16807]

That's not what Lavabit was ordered to do.

[bartbutler]

We don't store copies of plaintext emails indefinitely (it's obviously exists in the mail pipeline before processing). This statement is based on trust, as it would be for literally any email provider. That said, if we did store mails long term, they would be vulnerable to subpoena, and thus would almost certainly get out at some point, which would be very bad for us. So we have every incentive to actually discard plaintext, just like we say we do.

Obviously this does not apply to internal or external messages that are encrypted, so the real solution is to receive less unencrypted mail, which is exactly what today's announcement is about.

[Sir_Cmpwn]

>We don't store copies of plaintext emails indefinitely

We have to take your word for it. Genuinely secure systems don't require trust. Now, I think this feature is a genuinely good one and applaud you for it, but I've seen Protonmail reps lean on it as an excuse for why they can't support IMAP and SMTP, which is nonsense. I also think that users should be educated about the difference between security guarantees (which this isn't) and security promises (which this is).

Your incentives may be aligned in a way that means you'll want to avoid storing plaintext email, but it's entirely possible you could be compelled by your government to secretly start siphoning off plaintext. This is why it's necessary to design systems which don't ask for trust at all, and to educate users on the limitations of encrypting incoming emails.

[bartbutler]

1. We do support IMAP and SMTP, via the bridge.

2. We don't believe such compulsion would be legal and would fight it in court.

3. Yes, this is a security promise not a verifiable guarantee. As I said though, our incentives for this are correct. We would love more than anything for all email to be encrypted already. Signal and Wire require trust-on-first-use. There's always some small degree of trust, and the smaller the better. Given the reality of unencrypted email, this is the best we (and anyone else) can do. Whether you are comfortable with it is up to you and your threat model.

[Sir_Cmpwn]

>We do support IMAP and SMTP, via the bridge.

Do I need to repeat why I'm not going to take this argument yet again?

>We don't believe such compulsion would be legal and would fight it in court

Good to hear, but you should still be honest about the limitations in your approach. Secure systems are not built around trust and ones that are should not be advertised as such.

[gruez]

>We have to take your word for it. Genuinely secure systems don't require trust.

and what is this "Genuinely secure system" you speak of? as long as the sender is sending in plain text, your mail provider can intercept and record it. how are you going to communicate with the 99.9% of people/companies out there that don't PGP encrypt their outgoing mail?

[Sir_Cmpwn]

Right. I'm saying it's not possible, and that Protonmail should be honest about the limitations with their approach, so that people who have stricter security needs than are met by their threat model don't mistake their system for anything more secure than it is. Their home page has the following text:

>All emails are secured automatically with end-to-end encryption. This means even we cannot decrypt and read your emails. As a result, your encrypted emails cannot be shared with third parties.

This is a lie.