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Re:The PGP Problem by Sniffnoy on Wednesday July 17, 2019 @12:10AM (#20456373)
So what do I use for encrypted messaging that can, like, replace email, then? Nobody seems to have provided any sort of satisfactory answer to this question. To be clear, an answer this has to not just be a secure way of sending messages, it also has to replicate the social affordances of email.

E.g., things distinguishing how email is used from how text-messaging is used:

1. Email is potentially long-form. I sit down and type it from my computer. Text-messaging is always short, although possibly it's a series of short messages. A series of short emails, by contrast, is an annoyance; it's something you try to avoid sending (even though you inevitably do when it turns out you got something wrong). Similarly, you don't typically hold rapid-fire conversations over email.

2. On that point, email says, you don't need to read this immediately. I expect a text message will be probably be read in a few minutes, and probably replied to later that day (if there's no particular urgency). I expect an email will be probably read in a few hours, and probably replied to in a few days (if there's no particular urgency).

3. It's OK to cold-email people. To text someone you need their phone number; it's for people you know. By contrast, email addresses are things that people frequently make public specifically so that strangers can contact them.

So what am I supposed to do for secure messaging that replicates that? The best answer I've gotten for this so far -- other than PGP which is apparently bad -- is "install Signal on your computer in addition to your phone and just use it as if it's email". That's... not really a satisfactory answer. Like, I expect a multi-page Signal message talking about everything I've been up to for the past month to annoy its recipient, who is likely reading it on their phone, not their computer. And I can't send someone a Signal message about a paper they wrote that I have some comments on, not unless they're going to put their fricking phone number on their website.

So what do I do here? The secure email replacement just doesn't seem to be here yet.

Re:The PGP Problem by JasonFruit on Wednesday July 17, 2019 @01:27AM (#20456740)
Your point 1 especially speaks to me. Phone-based messaging in general isn't appropriate for the things I would most like to be kept private between me and a recipient, because those sorts of things can't be created on a phone. I've found PGP pretty good for making that happen, when I'm working with someone who a) uses PGP also and b) exercises some caution when using it. I haven't found an option that I can trust that will work for me.
Re:The PGP Problem by NoGravitas on Wednesday July 17, 2019 @08:19AM (#20458614)
I strongly agree with this; email is not instant messaging, and there is not yet any secure replacement for email.

We need a modern design for a successor protocol to email, and no one is working on it because they prefer instant messaging (or think other people do).

Re:The PGP Problem by amki on Wednesday July 17, 2019 @02:07PM (#20462354)
Google has tried with Wave but failed. I don't think it can be done.

Everything would have to support SMTP as a fallback for the lot of people that just don't care and thus couldn't actually improve.

Re:The PGP Problem by Natanael_L on Wednesday July 17, 2019 @08:50AM (#20458844)
I think we're more likely to "accidentally" end up there via E2EE document collaboration tools that are in development now.

One day, a while after they become usable and common, people will just realize they've been sharing documents E2EE in place of sending email, and they'll be using it for basically everything that matters.

It would be a proper restart and allow for significant improvements in usability and security and everything else.

Re:The PGP Problem by NoGravitas on Wednesday July 17, 2019 @08:59AM (#20458903)
Can you point me to examples of such tools?
Re:The PGP Problem by Natanael_L on Wednesday July 17, 2019 @09:25AM (#20459155)
Still under active development, nothing is really ready to use yet
Re:The PGP Problem by lvh on Wednesday July 17, 2019 @12:13AM (#20456396)
Do you feel like PGP is a good way to cold email people in practice? (I'm not trying to put words in your mouth, but that sounds like what you're saying.)
Re:The PGP Problem by tombrossman on Wednesday July 17, 2019 @05:48AM (#20457861)
> Do you feel like PGP is a good way to cold email people in practice?

Not OP but I can definitely say that's a yes from me after doing this repeatedly. I cold email people once a month or so, and if it is to do with anything sensitive I'll check to see if a public key is available for them (on their website is best, else I check a public key server and use that key as long as there is only one listed).

I get a better response rate from PGP/GPG users too, I can only recall one not responding to an encrypted message and I sent a follow-up message unencrypted which they responded to.

I think it's important to send PGP messages for ordinary communications whenever possible, because this normalizes it and may increase the workload for those trying to defeat it.

Re:The PGP Problem by Sniffnoy on Wednesday July 17, 2019 @12:22AM (#20456434)
Good question. Not sure. Although I don't see why I wouldn't, if they have a PGP key listed? (I guess there is some question over whether the listed key is actually them?) But my point is that, well, email is a good way to do that, and Signal isn't, so I'm going to use email rather than Signal.

Honestly, I wouldn't focus on (3), because as I see it, if you can replicate the feel of email, things like (1)-(2), so that it can replace email in contexts without (3), then (3) will just come naturally as it slowly replaces email.

Edit: All this is assuming it isn't tied to a phone number or something similar, of course!

Re:The PGP Problem by simonh on Wednesday July 17, 2019 @02:04AM (#20456910)
How does one list a public PGP key, is there a verified central listing service?
Re:The PGP Problem by jlgaddis on Wednesday July 17, 2019 @04:59AM (#20457694)
One of the major features of PGP is that you don't have to rely on -- trust -- a "verified central listing service".

The "Web of Trust" [0] fills that role:

> As time goes on, you will accumulate keys from other people that you may want to designate as trusted introducers. Everyone else will each choose their own trusted introducers. And everyone will gradually accumulate and distribute with their key a collection of certifying signatures from other people, with the expectation that anyone receiving it will trust at least one or two of the signatures. This will cause the emergence of a decentralized fault-tolerant web of confidence for all public keys.

[0]: https://en.wikipedia.org/wiki/Web_of_trust

Re:The PGP Problem by zaphar on Wednesday July 17, 2019 @09:48AM (#20459409)
In practice a web of trust is only trustworthy 1 degree out from you. Just because you trust someone doesn't mean you should trust the people they trust. The web of trust is a difficult to use misfeature. In theory it's great. In practice it's unusable.
Re:The PGP Problem by Natanael_L on Wednesday July 17, 2019 @08:52AM (#20458852)
The problem is nobody uses this right
Re:The PGP Problem by nindwen on Wednesday July 17, 2019 @05:06AM (#20457723)
If you control your own domain, Web Key Directory [0] is a good option too.

[0]: https://wiki.gnupg.org/WKD

Re:The PGP Problem by meruru on Wednesday July 17, 2019 @02:25AM (#20457009)
You can put it on your website or anywhere really. Some people use keybase.io for this.
Re:The PGP Problem by jobigoud on Wednesday July 17, 2019 @04:48AM (#20457645)
You can't put it anywhere really, otherwise anyone could tie their key to your identity. Keybase.io is a good solution.
Re:The PGP Problem by meruru on Wednesday July 17, 2019 @03:07PM (#20462936)
You're technically correct of course.
Re:The PGP Problem by Leace on Wednesday July 17, 2019 @04:58AM (#20457689)
I guess they mean putting the key on a webpage or using Web Key Directory or a centralized service such as https://keys.openpgp.org
Re:The PGP Problem by roel_v on Wednesday July 17, 2019 @02:52AM (#20457139)
There used to be a bunch of those in the 90s and it was a mess.
Re:The PGP Problem by bigiain on Wednesday July 17, 2019 @02:00AM (#20456889)
"mostly cold" email to a security email address listed on a website is probably the only use I've ever had to PGP encrypting email to someone I hadn't already been communicating with... (But I can imagine other scenarios. I bet Snowden's cold email to Greenwald was encrypted...)
Re:The PGP Problem by belorn on Wednesday July 17, 2019 @03:38AM (#20457333)
Trust on first use is not an uncommon security practice. Imperfect but in many times the best alternative, and a good solution while we wait for a replacement to gain traction.
Re:The PGP Problem by meruru on Wednesday July 17, 2019 @02:23AM (#20456996)
Why wouldn't it be?
Re:The PGP Problem by floatingatoll on Wednesday July 17, 2019 @01:51AM (#20456853)
3 is incorrect for encrypted email: you cannot email someone unaware without their consent and expect them to willingly and ably participate in decrypting.
Re:The PGP Problem by Sniffnoy on Wednesday July 17, 2019 @01:57AM (#20456877)
Why not? I mean, that's what publicly listing your public key is for, right?
Re:The PGP Problem by floatingatoll on Wednesday July 17, 2019 @02:02AM (#20456903)
Nope. I have at least three public never-expiring keys that I am unable revoke and that remain listed as valid because the keyservers don’t occasionally revalidate proof of ability to decrypt.
Re:The PGP Problem by PeterisP on Wednesday July 17, 2019 @03:31AM (#20457307)
Well, the keyservers also don't validate if it's your key instead of a key submitted by me with your email address on it, so for any secure messaging you need some other, authenticated channel for the potential recipient to assert which is their key.
Re:The PGP Problem by Sniffnoy on Wednesday July 17, 2019 @03:02AM (#20457182)
Oh, that's a good point. Heh, I have one of those, too, which even caused a problem once[0]. I wouldn't expect people to find it first, though, because I wouldn't expect people to go to a keyserver first; I'd expect them to find my key on one of the places I have it listed on the web. I've never tried blindly entering someone's email address into a keyserver and just hoping they have a key; I've only sent PGP-encrypted email to people who list their keys on the web.

[0]How it caused a problem: I added an email address to my public key (or maybe it expired or something, I forget), and asked people to refresh their copy of my key. One person instead downloaded it entirely anew from a keyserver and got the old one. Oops. (Admittedly I didn't explicitly use the word "refresh".) Anyway yeah -- though this problem had happened to me, it hadn't ocurred to me that it might be common; maybe this is more of a problem than I thought...

Re:The PGP Problem by floatingatoll on Wednesday July 17, 2019 @03:44AM (#20457366)
GPG chooses the key to use based on alphanumeric ordering of the short key ID, last time I experimented anyways. Best of luck overcoming that!
Re:The PGP Problem by gsich on Wednesday July 17, 2019 @02:19AM (#20456977)
>never-expiring keys

While this is bad, the keyserver issue is still valid.

Re:The PGP Problem by umvi on Wednesday July 17, 2019 @12:17AM (#20456412)
I don't get what's insecure about normal unencrypted email. It's sent over https, isn't it? It's not like I can read your emails unless I break into Google's servers, no? And even if I do, they probably aren't even stored in plaintext.

I just don't get the encrypted email obsession. It's impossible for an individual to withstand a targetted cyber attack so it seems pointless to go above and beyond to ultra encrypt every little thing

Re:The PGP Problem by thayne on Wednesday July 17, 2019 @02:01AM (#20456898)
> It's not like I can read your emails unless I break into Google's servers, no?

Well, first of all, "breaking in" isn't the only way someone might get access to data on Google's servers. There are such thing's as subpoenas, not to mention that it is possible a Google employee might abuse access to servers. And then I would be _very_ surprised if google doesn't use the content of your emails for advertisement and tracking purposes.

Furthermore, unless both parties are using gmail, the email will be stored at least temporarily on other mail servers, which may be less secure (and you might not even know who controls them).

Re:The PGP Problem by wodenokoto on Wednesday July 17, 2019 @02:21AM (#20456987)
> And then I would be _very_ surprised if google doesn't use the content of your emails for advertisement and tracking purposes.

That would go against their own privacy policy. But they are one change away from doing it.

Re:The PGP Problem by garmaine on Wednesday July 17, 2019 @02:27AM (#20457025)
Really? When gmail came out they were explicitly up front about using the content of the email to deliver targeted ads. Has that changed?
Re:The PGP Problem by riquito on Wednesday July 17, 2019 @03:03AM (#20457185)
There are a lot of misinformations around, and the Google haters crowd has plenty of pitchforks.

https://safety.google/privacy/ads-and-data/

> Google does not use keywords or messages in your inbox to show you ads. Nobody reads your email in order to show you ads.

Re:The PGP Problem by comex on Wednesday July 17, 2019 @03:16AM (#20457235)
It's not misinformation. Gmail only stopped scanning messages for ad targeting in 2017:

https://www.nytimes.com/2017/06/23/technology/gmail-ads.html

Re:The PGP Problem by alxlaz on Wednesday July 17, 2019 @05:12AM (#20457748)
It's just the passage of time that has rendered it misinformation. Until not so long ago, Gmail messages were actually scanned for ads -- IIRC, Google was actually pretty upfront about it when they first launched Gmail, and explained that it's how they could afford to give users 1G of inbox space in a day and age where 25 MB was pretty good and 100 MB was pretty hard to get for free.

They eventually stopped, although the phrasing of the privacy policy is vague enough that, as wodenokoto mentions above, I wouldn't be surprised if email messages were still scanned for some advertising purposes. The fragment on the page you link to is only about ads shown in Gmail, doesn't exclude using keywords and messages for tracking, classifying etc. (it just doesn't use them "to show you ads") and doesn't actually exclude using programs to process messages (i.e. you can still reasonably say that "nobody reads" messages if you just feed them into a program). It's also not very obvious if "messages in your inbox" also includes messages you send.

FWIW, I think the policy is deliberately open-ended so as to be future-proof, but I doubt emails are an important source of advertising data today, so I think it's likely that Google doesn't rely on it that much anymore. Most sources of legitimate (i.e. non-spam email) that are useful for advertising -- e.g. online shops and the like -- already track you and show you ads, and Google is already deeply embedded there. Millions and millions of personal accounts are an useful strategic asset to have but I think there are better sources of data.

Re:The PGP Problem by newscracker on Wednesday July 17, 2019 @06:37AM (#20458061)
> I doubt emails are an important source of advertising data today, so I think it's likely that Google doesn't rely on it that much anymore.

I completely disagree with the first part of your assertion. Email is still the main medium for all organizations, especially private companies taking your money for something, to communicate with you with plenty of details. Be it ordering some product online or booking a flight or other travel ticket or ordering a service or anything else.

The richness and amount of information conveyed over email pales in comparison to SMS notifications. So email is still a treasure trove of what people are doing and have done.

Re:The PGP Problem by alxlaz on Thursday July 18, 2019 @04:11AM (#20467820)
> Be it ordering some product online or booking a flight or other travel ticket or ordering a service

That's true, but all these places already track the living hell out of you. Even the newsletters they send over email have tracking information. By the time they've sent you an email after your first purchase, they know everything they need to show you relevant ads (in fact, that's probably why you made the first purchase...). I doubt bulk analysis of emails can show anything that is not already known way before the emails got sent.

Re:The PGP Problem by megous on Wednesday July 17, 2019 @12:56PM (#20461531)
Depends on what they mean by messages? The whole raw message, incl. all headers? The text user sees?

Google can probably serve nice ads just based on metadata it gathers on the SMTP level, without even using the raw message. Someone mails his bank, maybe show some banking related e-mails, etc.

And it would still stay true to the proclamation on that page.

Re:The PGP Problem by away_throw on Wednesday July 17, 2019 @11:22AM (#20460424)
Are we sure about this? When I downloaded my Google data, I fished around and found information related to my Amazon purchase history and etcetera. The only possible way that I can think of that Google is able to get my purchase data is from my email.
Re:The PGP Problem by BeetleB on Wednesday July 17, 2019 @11:29AM (#20460513)
That's not misinformation - it's just mildly dated information. Google stopped scanning emails for ads very recently.

It was never a conspiracy theory. Google used to be very open about the fact that they were scanning emails.

Re:The PGP Problem by wodenokoto on Wednesday July 17, 2019 @02:29PM (#20462582)
Yes when.

What changed was gsuit. They want to move away from the “we are harvesting your emails” image, in order to better sell paid accounts

“Consumer Gmail content will not be used or scanned for any ads personalization after this change.”

https://blog.google/products/gmail/g-suite-gains-traction-in...

Re:The PGP Problem by justincormack on Wednesday July 17, 2019 @02:52AM (#20457144)
If you pay Google for email they will not use the content for ads. Free accounts I think they still do.
Re:The PGP Problem by jcranmer on Wednesday July 17, 2019 @12:22AM (#20456436)
In modern practice, email is sent over TLS sockets already. Any good email client should prohibit you from using SMTP, POP, or IMAP with TLS, and for the past few years, even the MX-MX transfers in the backend have started to become protected (albeit mostly opportunistically at this point, I believe) with TLS.

So the only people who can read email are you, your counterparty, your ESP, and your counterparty's ESP, assuming the email providers are following good practice.

Re:The PGP Problem by Godel_unicode on Wednesday July 17, 2019 @01:44AM (#20456820)
This is an excellent explanation overall, I do however think that it's important to note that opportunistic STARTTLS is vulnerable to downgrade attacks by mitm. Since this would have to be a mitm of e.g. Gmail it's not trivial by any means, but neither is it completely out of reach (see for example the periodic rerouting of the internet caused by odd BGP advertisements).

One further note is that you can know post-hoc if an email was delivered to Gmail via TLS by the presence or absence of a red lock in the Gmail app or web UI.

Re:The PGP Problem by bigiain on Wednesday July 17, 2019 @01:57AM (#20456878)
> STARTTLS is vulnerable to downgrade attacks by mitm.

Not only that, but intentionally downgrading STARTTLS commands has as times been the default configuration for some Cisco routing gear.

(Buy me a beer one day and I might tell you about the time I charged one of Australia's big four banks about $70k to debug that in a router on their internal network that nobody there knew existed...)

Re:The PGP Problem by jlgaddis on Wednesday July 17, 2019 @02:01PM (#20462284)
Which routers did that? I'm well aware that the ASA firewalls did it ("ESMTP inspection") -- I've disabled that dozens of times -- but I've never heard of a router that did it (by default).
Re:The PGP Problem by tialaramex on Wednesday July 17, 2019 @04:29AM (#20457567)
This is often explained in a needlessly confusing way.

STARTTLS isn't a problem, the problem is if a user checks a box (or moral equivalent) saying it's optional obviously bad guys will opt for "No". If your client is set to _require_ STARTTLS, then an adversary blocking STARTTLS has the same effect as if they just blocked the IP address of the mail server, you get an error and it doesn't work.

There's no reason to use "opportunistic" STARTTLS for your own mail servers (ie IMAP or SMTP to an outbound relay). Nobody should be configuring their own gear, or corporate gear, to just let somebody else decide whether it uses encryption.

Opportunistic encryption still has a place in server-to-server SMTP relaying, but if you're choosing options like "if available" in a desktop/phone mail client that's wrong.

Re:The PGP Problem by geocar on Wednesday July 17, 2019 @04:49AM (#20457654)
It may be better than nothing, but it's far from a sure thing: If you can BGP announce an IP, you can get a certificate from letsencrypt.

This is a trivial attack vector not just for state-actors, but also stupid kids: in the early 2000s, I announced Microsoft's AS from my own network (AS21863) to see what would happen and got a significant amount of microsoft.com's traffic. There was no security, and there still isn't: Most multihomed sites that change links frequently inevitably find themselves unfiltered either through accident or misplaced trust.

For this reason, TLS without key-pinning (even with IP filtering, as is popular with a lot of banks/enterprise) is far less secure than people realise, and on unattended links (server-to-server relaying) it offers only some casual confidentiality (since detection is unlikely) at best.

If you use MTA-STS, you have a good chance of detecting this kind of attack though. I've not seen anyone use a long policy on a distant but popular network to require someone BGP hijack two big networks to beat it, but I suspect such a disruption would be felt across the Internet.

Re:The PGP Problem by tinus_hn on Wednesday July 17, 2019 @07:14AM (#20458218)
Letsencrypt supposedly has deployed a system that makes the connections from different locations around the world to make this attack more difficult and also you can’t get a letsencrypt certificate for gmail.com or microsoft.com (or Gmail.* or microsoft.* for that matter), there’s a block list for high value targets.
Re:The PGP Problem by geocar on Thursday July 18, 2019 @11:36AM (#20470916)
I would hope letsencrypt has a number of heuristic safeguards, but I can guarantee they do not make connections from multiple routing paths: My ad server registers a certificate during the SNI hello (but before the certificate is presented), and I get a certificate after a single ping.
Re:The PGP Problem by throw0101a on Wednesday July 17, 2019 @03:00PM (#20462868)
> I do however think that it's important to note that opportunistic STARTTLS is vulnerable to downgrade attacks by mitm

See SMTP MTA Strict Transport Security (MTA-STS):

* https://tools.ietf.org/html/rfc8461

And STARTTLS Everywhere:

* https://starttls-everywhere.org/

Re:The PGP Problem by helper on Wednesday July 17, 2019 @03:08AM (#20457203)
MTA-STS prevents downgrade attacks.
Re:The PGP Problem by throw0101a on Wednesday July 17, 2019 @02:56PM (#20462847)
> Any good email client should prohibit you from

Most e-mail servers required a login (regardless of fetching or sending), and it would take a real incompetent sysadmin to allow that to happen in the clear.

Re:The PGP Problem by loup-vaillant on Wednesday July 17, 2019 @05:18AM (#20457762)
> It's sent over https, isn't it?

That's actually more complicated than that.

If you're using a web mail, your connection to the mail provider most likely uses HTTPS. That is, HTTP over TLS. When the mail is sent, it depends whether the recipient uses the same provider or not. If it's the same provider, well, protocols are irrelevant. If not, it will usually be SMTP over TLS (minus any potential problems with STARTTLS).

The main problem with that is that the mail is not encrypted on the various servers it goes through. Only the server-to-server connections are encrypted. So your provider can access your email, and so can the recipient's. When that provider's business model is reading your emails so it can send you targeted adds, this is less than great. (Yes, Google reads your emails. They try to reassure you by telling you their employees don't read it, but the fact the process is automated actually makes it worse.)

Re:The PGP Problem by __david__ on Wednesday July 17, 2019 @07:01AM (#20458165)
Also, it might surprise some people just how many servers an email travels through to get to its destination. I just grabbed a random mail from a mailing list I'm on (generally a worst case scenario) and it had 7 Received headers. Every mail server is supposed to add a Received header when the mail passes through but there's no way to enforce that, so all I can really say is that mail probably passed through at least 7 servers on it's way to my inbox.

Each one of those hops may or may not have talked TLS to the next hop. Each one probably wrote the mail out to a disk based mail queue in plaintext. There is nothing preventing any of those 7 servers from keeping around that mail even though they forwarded it on. There is nothing preventing them from indexing the mail for spam or marketing purposes.

Re:The PGP Problem by cmroanirgo on Wednesday July 17, 2019 @02:51AM (#20457137)
Any sysadmin can read your email, in general. There's no holistic "this email can't be read by anyone other than the recipient" as a solution, which is what a lot of us are aiming for. Things like protonmail and tutanota get really close, but they're proprietary solutions and don't work for "the many" (such as yourself) who use a hosted solution such as Gmail, who seem to have no interest in providing an open solution.
Re:The PGP Problem by meruru on Wednesday July 17, 2019 @02:20AM (#20456982)
I don't want my emails to be readable by Google, yet they will when people I communicate with are using Gmail.
Re:The PGP Problem by gsich on Wednesday July 17, 2019 @01:37AM (#20456786)
Mail doesn't use HTTPS. But even if TLS is enabled, you don't know that all the time.
Re:The PGP Problem by tinus_hn on Wednesday July 17, 2019 @07:05AM (#20458184)
The old ‘security is hard so let’s not do it’ argument. Emails are not properly encrypted in transit and are available for access at the provider if a court decides to grant a warrant. That might not be enough protection for everyone.

It is possible for a determined individual to withstand targeted attacks if he’s careful and willing to make the sacrifices that come with the territory.

Re:The PGP Problem by dasil003 on Wednesday July 17, 2019 @12:22AM (#20456437)
Are you assuming everyone uses Gmail or do you not know how SMTP works?
Re:The PGP Problem by Godel_unicode on Wednesday July 17, 2019 @01:37AM (#20456784)
You might be surprised just how many mail providers support STARTTLS for email, at least opportunistically.

https://www.fastmail.com/help/technical/ssltlsstarttls.html

Re:The PGP Problem by willvarfar on Wednesday July 17, 2019 @01:51AM (#20456848)
And opportunistic STARTTLS is vulnerable to downgrade attacks by MITM.

the problems with email are that, no matter how sure you are that the connection between you and your mail server, and your local and server storage, are secure, the parties you may be interacting with are not. And then, as is talked about in the article, your recipient forwards the mail as plaintext...

Re:The PGP Problem by delroth on Wednesday July 17, 2019 @08:04AM (#20458504)
And downgrade attacks are mitigated by MTA-STS: https://www.hardenize.com/blog/mta-sts

Not supported by everyone just yet since this is a new standard, but Gmail at least supports it.