11 ms·

Here's the best guess what I think would happen: Some large player - today it'd probably be Google, in the future maybe some other company - or a collection of

by hannob 7y ago

Here's the best guess what I think would happen: Some large player - today it'd probably be Google, in the future maybe some other company - or a collection of players would decide that it's in their best business interest not to let half of the open Internet go down. And they'd come to the conclusion that providing a replacement that's basically just "change this url in your ACME software and you can continue do things as before" doesn't cost them too much (Google already runs a CA, as do many other large IT corps) and they should do it.

ForHackernews 7y ago
Oh yeah, it'd be great if Google could MITM half the SSL on the internet...
- parliament32 7y ago
  Cloudflare already MITMs like 2/3 of the traffic on the internet. Personally I'd trust Google more than them. Google may be evil but at least their motives are clear.
  - ignoramous 7y ago
    > Cloudflare already MITMs like 2/3 of the traffic on the internet. Cloudflare (MiTM [0] or not) is on record that 10% (and not 66%) of the all internet traffic now flows through their networks. Ref: https://news.ycombinator.com/item?id=19204085 https://news.ycombinator.com/item?id=19204085 [0] https://blog.cloudflare.com/keyless-delegation/ https://blog.cloudflare.com/keyless-delegation/
- brainscdf 7y ago
  > Oh yeah, it'd be great if Google could MITM half the SSL on the internet... How exactly would Google MITM half the SSL on the internet by virtue of issuing certificates via ACME? The private key never leaves the subject's system (the system hosting a website for example). Google would never have access to the private key for which it would issue the public key certificate. Further, if Google abuses its power by issuing a fake certificate for another website and uses that to MITM all traffic to that website, all browsers and systems would remove the offending CA certificates from their trust store immediately. Look what happened to DigiNotar.
  - ignoramous 7y ago
    Not that I expect Google to issue fake certs, but DigiNotar also doesn't command 80%+ browser marketshare to soften the blowback.
    - brainscdf 7y ago
      > Not that I expect Google to issue fake certs, but DigiNotar also doesn't command 80%+ browser marketshare to soften the blowback. Not sure how that is relevant. DigiNotar was a trusted root CA in all major browsers. So if an attacker managed to get a fake certificate issued by DigiNotar, they could attack 100% of the users visiting the website for which the fake certificate was issued. In fact, they did issue fake certificates by accident due to a security breach. As soon as the error was caught, their CA certificates were removed from all browsers. They went bankrupt! That's how serious this business of issuing certificates is.
      - thenewnewguy 7y ago
        It's relevant because Google isn't likely to remove _themselves_ from their browser, which is currently the most popular web browser on the planet. For this reason alone, having a major browser dev as a CA is not a good idea, regardless of how much or little you trust google.
        jacobparker 7y ago
        Google is already a CA. https://pki.google.com https://pki.google.com
- Znafon 7y ago
  This is absolutly not how a certificate signing request work at all. Please don't say something so wrong just to scare people, you cannot read encrypted packets just because you signed a certificate.
- Roujo 7y ago
  As I understand it, a CA doesn't have a way of MITMing connections just by virtue of them being the one validating the cert for a certain website. You don't share the private keys of your certs when you generate them[0], you just need for a CA to attest that yes, this certificate's public key is allowed to be used for whatever use you're applying for. ACME doesn't change that, it just allows this verification to be done automatically. Let's Encrypt doesn't have any more ways of MITMing people using their certs than any other CA - that is, they _could_ do it by generating rogue certs, but that's no different than what Google can already do since they're a CA as well. Plus, certificate transparency logs should make it visible if they ever do so. 0: Barring weird cases I've seen of some companies letting you generate a cert entirely on their website, letting you download the private key once it's done. Which is bad practice for the reason you're talking about right now, since by then you have no assurance that they haven't kept a copy of that private key for later use.
  - chromaxs 7y ago
    Any CA can sign any certificate they want, including ones they generate themselves. If a bad actor got control of, or even could coerce, a CA, and could do the same for DNS, the end users would be hard pressed to know. It's a very valid attack, although minimal. To say they don't have any way of MITM'ing a connection is wrong even if it's unlikely.
    - iudqnolq 7y ago
      Wouldn't it be equally easy for a CA to MITM a site that got it's real cert from them vs from a different CA?
      - Roujo 7y ago
        CAA DNS records aim to make that more difficult, actually, but otherwise AFAIK you're right. =) https://en.wikipedia.org/wiki/DNS_Certification_Authority_Authorization https://en.wikipedia.org/wiki/DNS_Certification_Authority_Au...
        7y ago
- bananabreakfast 7y ago
  Yo, learn how cert signing works. That's not it.
  - syncsynchalt 7y ago
    Counterpoint to what you're saying: Any trusted CA can MITM almost any site on the internet (ignoring CA extensions like Name Restrictions, pinned certs, etc). Google has a trusted CA, so while the OP is wrong it's not something they can't do.
- hannob 7y ago
  That's not how CAs work.

by hannob 7y ago

ForHackernews 7y ago

Oh yeah, it'd be great if Google could MITM half the SSL on the internet...

parliament32 7y ago
Cloudflare already MITMs like 2/3 of the traffic on the internet. Personally I'd trust Google more than them. Google may be evil but at least their motives are clear.
- ignoramous 7y ago
  > Cloudflare already MITMs like 2/3 of the traffic on the internet. Cloudflare (MiTM [0] or not) is on record that 10% (and not 66%) of the all internet traffic now flows through their networks. Ref: https://news.ycombinator.com/item?id=19204085 https://news.ycombinator.com/item?id=19204085 [0] https://blog.cloudflare.com/keyless-delegation/ https://blog.cloudflare.com/keyless-delegation/
brainscdf 7y ago
> Oh yeah, it'd be great if Google could MITM half the SSL on the internet... How exactly would Google MITM half the SSL on the internet by virtue of issuing certificates via ACME? The private key never leaves the subject's system (the system hosting a website for example). Google would never have access to the private key for which it would issue the public key certificate. Further, if Google abuses its power by issuing a fake certificate for another website and uses that to MITM all traffic to that website, all browsers and systems would remove the offending CA certificates from their trust store immediately. Look what happened to DigiNotar.
- ignoramous 7y ago
  Not that I expect Google to issue fake certs, but DigiNotar also doesn't command 80%+ browser marketshare to soften the blowback.
  - brainscdf 7y ago
    > Not that I expect Google to issue fake certs, but DigiNotar also doesn't command 80%+ browser marketshare to soften the blowback. Not sure how that is relevant. DigiNotar was a trusted root CA in all major browsers. So if an attacker managed to get a fake certificate issued by DigiNotar, they could attack 100% of the users visiting the website for which the fake certificate was issued. In fact, they did issue fake certificates by accident due to a security breach. As soon as the error was caught, their CA certificates were removed from all browsers. They went bankrupt! That's how serious this business of issuing certificates is.
    - thenewnewguy 7y ago
      It's relevant because Google isn't likely to remove _themselves_ from their browser, which is currently the most popular web browser on the planet. For this reason alone, having a major browser dev as a CA is not a good idea, regardless of how much or little you trust google.
      - jacobparker 7y ago
        Google is already a CA. https://pki.google.com https://pki.google.com
Znafon 7y ago
This is absolutly not how a certificate signing request work at all. Please don't say something so wrong just to scare people, you cannot read encrypted packets just because you signed a certificate.
Roujo 7y ago
As I understand it, a CA doesn't have a way of MITMing connections just by virtue of them being the one validating the cert for a certain website. You don't share the private keys of your certs when you generate them[0], you just need for a CA to attest that yes, this certificate's public key is allowed to be used for whatever use you're applying for. ACME doesn't change that, it just allows this verification to be done automatically. Let's Encrypt doesn't have any more ways of MITMing people using their certs than any other CA - that is, they _could_ do it by generating rogue certs, but that's no different than what Google can already do since they're a CA as well. Plus, certificate transparency logs should make it visible if they ever do so. 0: Barring weird cases I've seen of some companies letting you generate a cert entirely on their website, letting you download the private key once it's done. Which is bad practice for the reason you're talking about right now, since by then you have no assurance that they haven't kept a copy of that private key for later use.
- chromaxs 7y ago
  Any CA can sign any certificate they want, including ones they generate themselves. If a bad actor got control of, or even could coerce, a CA, and could do the same for DNS, the end users would be hard pressed to know. It's a very valid attack, although minimal. To say they don't have any way of MITM'ing a connection is wrong even if it's unlikely.
  - iudqnolq 7y ago
    Wouldn't it be equally easy for a CA to MITM a site that got it's real cert from them vs from a different CA?
    - Roujo 7y ago
      CAA DNS records aim to make that more difficult, actually, but otherwise AFAIK you're right. =) https://en.wikipedia.org/wiki/DNS_Certification_Authority_Authorization https://en.wikipedia.org/wiki/DNS_Certification_Authority_Au...
      - 7y ago
bananabreakfast 7y ago
Yo, learn how cert signing works. That's not it.
- syncsynchalt 7y ago
  Counterpoint to what you're saying: Any trusted CA can MITM almost any site on the internet (ignoring CA extensions like Name Restrictions, pinned certs, etc). Google has a trusted CA, so while the OP is wrong it's not something they can't do.
hannob 7y ago
That's not how CAs work.