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Could someone explain to me the lore that email can't be make secure? It seems to me that all the steps described on this article could be automated behind the

Could someone explain to me the lore that email can't be make secure? It seems to me that all the steps described on this article could be automated behind the scenes by a good local email client.

tptacek 9y ago
* Email defaults and fails open to plaintext. Modern secure messengers only transmit securely. Even modern secure websites take pains, including extensions that had to be made to the HTTP protocol, to prevent traffic from being sent unencrypted. No such mechanism exists in email. * Email reveals large amounts of metadata, including message content (which is what a Subject: line is), which is a characteristic shared by no secure messaging system. The graph of who talks to who and when is immensely important, and the best secure messengers (Signal, in particular) go through trouble to obscure it. * Modern secure messengers are forward-secure, so that a compromised key doesn't allow attackers to retroactively decrypt old messages. Since messaging traffic between selected peers is almost always low-volume, any reasonable threat model assumes every piece of ciphertext exchanged between peers has been archived by adversaries. With PGP, a key compromise at any point in time reveals the contents of every one of those messages. The best secure messaging systems are not only forward secure but also have a notion of "future secrecy" allowing them to recover from ephemeral key loss. * Email clients are inhospitable to cryptography; in particular, many of key features of clients (like search) rely on having a local archive of plaintext. The UX in email clients begs users for catastrophic failure, like accidentally top-posting a reply to an encrypted messages with an unencrypted message. All four of these problems are, in isolation, total dealbreakers for serious secure messaging. SMTP email is janky and outmoded and it's a little amazing that we all use it as much as we do; it's long overdue for a replacement. If you need to communicate securely with someone else, you should do so with a secure messenger like Signal, not with PGP and email.
- RasputinsBro 9y ago
  So why is it that people like Assange and Snowden, whose lives arguably depend on these matters, choose PGP over anything else? I'm no expert in security, but my intuition is that the likelihood that my signed ubuntu plus gpg leak secrets is significantly lower than my who-knows-what-the-hell-its-doing android with signal, right? You gotta agree with this at least.
  - tptacek 9y ago
    Because contrary to their public images neither is in fact a subject matter expert on these topics. Snowden in particular did much dumber things than using PGP: he used Lavabit, a "secure email provider" with an architecture any expert could have told you from 10 miles away to avoid, and some amount of the Snowden/Poitras/Greenwald coordination occurred over CryptoCat, which was grievously broken in several different ways --- it is almost certain that every message exchanged between those parties on CryptoCat has been recovered by SIGINT agencies. People wonder why crypto engineers on message boards are so shrill about this stuff. This is why.
    - RasputinsBro 9y ago
      Yeah, experts also tell you to avoid any mobile OS and you're claiming that Signal is the best secure messenger. What am I missing here?
      - forapurpose 9y ago
        > experts also tell you to avoid any mobile OS Experts I know recommend iOS above any other consumer platform (though that might have something to do with Apple's hardware and of course you can't use iOS without Apple hardware).
        RasputinsBro 9y ago
        So the experts you know recommend a closed-source OS? They recommend something that no one has any idea what's inside above ANY OTHER consumer platform? You're joking, right? Can you put me in touch with these experts? I'd like to ask them about it directly.
        forapurpose 9y ago
        Personally, I strongly prefer FOSS for many reasons. IME, real security experts are not so focused on that issue. Saying that nobody knows what is inside is a large exaggeration and an over-emphasis on one factor.
- sliken 9y ago
  I agree, email sucks. However it seems like a reasonable goal to improve it. Signal started out with SMS, which was quickly abandoned. Your target would basically get a SMS message saying something like "someone is sending you an encrypted message, please install signal to read it". Seems like a imap proxy could do similar. Use a DHT to track who has a public key. Send anyone who doesn't a "please install this plugin/proxy/whatever to read this message". Have a signal like autogeneration of keys tied to an email address instead of signal's phone number. Could even have a service like <username>@whisper.com to allow people to use their favorite email client (like thunderbird) to send/receive email and leak less metadata. The imap proxy would use a signal like transport for anything matching @whisper.com. I seem to recall a project like this mentioned, even a thunderbird plugin or some such. Not as secure as signal, but better than today's default.
  - tptacek 9y ago
    It's hard to understand why we'd spend effort pushing for adoption of a rube goldberg machine that can only hope to approach the security of Signal when we could instead just have people adopt Signal.
    - sliken 9y ago
      Signal needs quite a bit of work to be as useful as email. No choice in clients, requiring a cell number, no search, and no threads. Hard to imagine someone that uses email heavily with large volume of email trying to cram that much information into signal and then be able to find it again years later.
      - tptacek 9y ago
        The vast, overwhelming majority of email users --- who also encompass the vast, overwhelming majority of users with serious privacy needs, contrary to the opinion of "privacy nerds" --- use whichever email client they were first introduced to, never change clients, and don't use any of the advanced features in those clients. Those are the users who are better served by Signal than by some janky attempt to make email almost perhaps under the best circumstances 60% as secure as Signal.

Could someone explain to me the lore that email can't be make secure? It seems to me that all the steps described on this article could be automated behind the scenes by a good local email client.

tptacek 9y ago

* Email defaults and fails open to plaintext. Modern secure messengers only transmit securely. Even modern secure websites take pains, including extensions that had to be made to the HTTP protocol, to prevent traffic from being sent unencrypted. No such mechanism exists in email. * Email reveals large amounts of metadata, including message content (which is what a Subject: line is), which is a characteristic shared by no secure messaging system. The graph of who talks to who and when is immensely important, and the best secure messengers (Signal, in particular) go through trouble to obscure it. * Modern secure messengers are forward-secure, so that a compromised key doesn't allow attackers to retroactively decrypt old messages. Since messaging traffic between selected peers is almost always low-volume, any reasonable threat model assumes every piece of ciphertext exchanged between peers has been archived by adversaries. With PGP, a key compromise at any point in time reveals the contents of every one of those messages. The best secure messaging systems are not only forward secure but also have a notion of "future secrecy" allowing them to recover from ephemeral key loss. * Email clients are inhospitable to cryptography; in particular, many of key features of clients (like search) rely on having a local archive of plaintext. The UX in email clients begs users for catastrophic failure, like accidentally top-posting a reply to an encrypted messages with an unencrypted message. All four of these problems are, in isolation, total dealbreakers for serious secure messaging. SMTP email is janky and outmoded and it's a little amazing that we all use it as much as we do; it's long overdue for a replacement. If you need to communicate securely with someone else, you should do so with a secure messenger like Signal, not with PGP and email.

RasputinsBro 9y ago
So why is it that people like Assange and Snowden, whose lives arguably depend on these matters, choose PGP over anything else? I'm no expert in security, but my intuition is that the likelihood that my signed ubuntu plus gpg leak secrets is significantly lower than my who-knows-what-the-hell-its-doing android with signal, right? You gotta agree with this at least.
- tptacek 9y ago
  Because contrary to their public images neither is in fact a subject matter expert on these topics. Snowden in particular did much dumber things than using PGP: he used Lavabit, a "secure email provider" with an architecture any expert could have told you from 10 miles away to avoid, and some amount of the Snowden/Poitras/Greenwald coordination occurred over CryptoCat, which was grievously broken in several different ways --- it is almost certain that every message exchanged between those parties on CryptoCat has been recovered by SIGINT agencies. People wonder why crypto engineers on message boards are so shrill about this stuff. This is why.
  - RasputinsBro 9y ago
    Yeah, experts also tell you to avoid any mobile OS and you're claiming that Signal is the best secure messenger. What am I missing here?
    - forapurpose 9y ago
      > experts also tell you to avoid any mobile OS Experts I know recommend iOS above any other consumer platform (though that might have something to do with Apple's hardware and of course you can't use iOS without Apple hardware).
      - RasputinsBro 9y ago
        So the experts you know recommend a closed-source OS? They recommend something that no one has any idea what's inside above ANY OTHER consumer platform? You're joking, right? Can you put me in touch with these experts? I'd like to ask them about it directly.
        forapurpose 9y ago
        Personally, I strongly prefer FOSS for many reasons. IME, real security experts are not so focused on that issue. Saying that nobody knows what is inside is a large exaggeration and an over-emphasis on one factor.
sliken 9y ago
I agree, email sucks. However it seems like a reasonable goal to improve it. Signal started out with SMS, which was quickly abandoned. Your target would basically get a SMS message saying something like "someone is sending you an encrypted message, please install signal to read it". Seems like a imap proxy could do similar. Use a DHT to track who has a public key. Send anyone who doesn't a "please install this plugin/proxy/whatever to read this message". Have a signal like autogeneration of keys tied to an email address instead of signal's phone number. Could even have a service like <username>@whisper.com to allow people to use their favorite email client (like thunderbird) to send/receive email and leak less metadata. The imap proxy would use a signal like transport for anything matching @whisper.com. I seem to recall a project like this mentioned, even a thunderbird plugin or some such. Not as secure as signal, but better than today's default.
- tptacek 9y ago
  It's hard to understand why we'd spend effort pushing for adoption of a rube goldberg machine that can only hope to approach the security of Signal when we could instead just have people adopt Signal.
  - sliken 9y ago
    Signal needs quite a bit of work to be as useful as email. No choice in clients, requiring a cell number, no search, and no threads. Hard to imagine someone that uses email heavily with large volume of email trying to cram that much information into signal and then be able to find it again years later.
    - tptacek 9y ago
      The vast, overwhelming majority of email users --- who also encompass the vast, overwhelming majority of users with serious privacy needs, contrary to the opinion of "privacy nerds" --- use whichever email client they were first introduced to, never change clients, and don't use any of the advanced features in those clients. Those are the users who are better served by Signal than by some janky attempt to make email almost perhaps under the best circumstances 60% as secure as Signal.