4 ms·

The CA system and WebPKI is more or less fundamentally flawed. - Too few CAs and you loose on competition. - Too many CAs and the probability of vulnerabiliti

The CA system and WebPKI is more or less fundamentally flawed. - Too few CAs and you loose on competition. - Too many CAs and the probability of vulnerabilities approaches 100%.

ocdtrekkie 4y ago
This is the correct take. There's a bunch of policies and practices but essentially dozens of shady providers have complete ability to impersonate anyone on the web, and the behavior of those policies and practices is set by a might-makes-right of the most popular browser vendors. The entire system is equal parts insecure and absolutely impractical, such that 80% of organization have had an outage caused by certificate issues but certificates aren't meaningfully providing security.
woodruffw 4y ago
"Competition" is not a desirable property in a cryptosystem. The fact that it's a property of WebPKI at all is a historical quirk of CA organizational practices and the (entirely artificial) market for certificates. In other words: we should be seriously cutting down the number of trusted CAs.
- kevincox 4y ago
  The problem is that CAs aren't really part of the cryptosystem. They hold the roots of trust but charge for there services and are for-profit. Without any competition we would have a terrible monopoly. I agree that there are too many CAs. But the ideal number is also significantly more than 1. ...well unless you include zero. If we can replace this with something better that would be much more desirable.
  - woodruffw 4y ago
    How so? The cryptosystem in question is WebPKI. CAs form the roots of trust in WebPKI, as you mentioned. > They hold the roots of trust but charge for there services and are for-profit. Without any competition we would have a terrible monopoly. This hasn't been true for years! Let's Encrypt provides free certificates to anyone with a domain. They issue millions of certs a day and secure a massive chunk of the web[1]. I think everybody is in broad agreement that the CA system is brittle, vulnerable to mismanagement, bad actors, etc. But "something better" is very hard to identify and implement. Churchill's saying about the "worse system except for all the others"[1] applies equally well here, IMO. [1]: https://blogs.fcdo.gov.uk/petermillett/2014/03/05/the-worst-form-of-government/ https://blogs.fcdo.gov.uk/petermillett/2014/03/05/the-worst-... [1]: https://www.linuxfoundation.org/resources/case-studies/lets-encrypt https://www.linuxfoundation.org/resources/case-studies/lets-...
    - luckylion 4y ago
      > This hasn't been true for years! Let's Encrypt provides free certificates to anyone with a domain. Because they are the competition.
      - woodruffw 4y ago
        The point being that the monopoly's back has been broken. We're no longer in a situation where there needs to be >100 CAs for market competition purposes; there's now a free, universally available, public service.
        lmm 4y ago
        Is LE really universally available? I'm not aware of them making any public commitment to serve unpopular websites (thinking of e.g. KiwiFarms), and they used to check an opaque Google blacklist before issuing certificates.
        woodruffw 4y ago
        They list no stipulations about prohibited certificate uses[1]. Their restrictions on domain uses seem to be mostly tied to legal requirements (not issuing for sanctioned countries, for example). It's all also pretty transparent, from what I can tell[2][3]. Certainly more so than a normal CA. [1]: https://letsencrypt.org/documents/isrg-cp-v3.3/#1.4.2-prohibited-certificate-uses https://letsencrypt.org/documents/isrg-cp-v3.3/#1.4.2-prohib... [2]: https://letsdebug.net/ https://letsdebug.net/ [3]: https://github.com/letsdebug/letsdebug https://github.com/letsdebug/letsdebug

The CA system and WebPKI is more or less fundamentally flawed. - Too few CAs and you loose on competition. - Too many CAs and the probability of vulnerabilities approaches 100%.

ocdtrekkie 4y ago

This is the correct take. There's a bunch of policies and practices but essentially dozens of shady providers have complete ability to impersonate anyone on the web, and the behavior of those policies and practices is set by a might-makes-right of the most popular browser vendors. The entire system is equal parts insecure and absolutely impractical, such that 80% of organization have had an outage caused by certificate issues but certificates aren't meaningfully providing security.

woodruffw 4y ago

"Competition" is not a desirable property in a cryptosystem. The fact that it's a property of WebPKI at all is a historical quirk of CA organizational practices and the (entirely artificial) market for certificates. In other words: we should be seriously cutting down the number of trusted CAs.

kevincox 4y ago
The problem is that CAs aren't really part of the cryptosystem. They hold the roots of trust but charge for there services and are for-profit. Without any competition we would have a terrible monopoly. I agree that there are too many CAs. But the ideal number is also significantly more than 1. ...well unless you include zero. If we can replace this with something better that would be much more desirable.
- woodruffw 4y ago
  How so? The cryptosystem in question is WebPKI. CAs form the roots of trust in WebPKI, as you mentioned. > They hold the roots of trust but charge for there services and are for-profit. Without any competition we would have a terrible monopoly. This hasn't been true for years! Let's Encrypt provides free certificates to anyone with a domain. They issue millions of certs a day and secure a massive chunk of the web[1]. I think everybody is in broad agreement that the CA system is brittle, vulnerable to mismanagement, bad actors, etc. But "something better" is very hard to identify and implement. Churchill's saying about the "worse system except for all the others"[1] applies equally well here, IMO. [1]: https://blogs.fcdo.gov.uk/petermillett/2014/03/05/the-worst-form-of-government/ https://blogs.fcdo.gov.uk/petermillett/2014/03/05/the-worst-... [1]: https://www.linuxfoundation.org/resources/case-studies/lets-encrypt https://www.linuxfoundation.org/resources/case-studies/lets-...
  - luckylion 4y ago
    > This hasn't been true for years! Let's Encrypt provides free certificates to anyone with a domain. Because they are the competition.
    - woodruffw 4y ago
      The point being that the monopoly's back has been broken. We're no longer in a situation where there needs to be >100 CAs for market competition purposes; there's now a free, universally available, public service.
      - lmm 4y ago
        Is LE really universally available? I'm not aware of them making any public commitment to serve unpopular websites (thinking of e.g. KiwiFarms), and they used to check an opaque Google blacklist before issuing certificates.
        woodruffw 4y ago
        They list no stipulations about prohibited certificate uses[1]. Their restrictions on domain uses seem to be mostly tied to legal requirements (not issuing for sanctioned countries, for example). It's all also pretty transparent, from what I can tell[2][3]. Certainly more so than a normal CA. [1]: https://letsencrypt.org/documents/isrg-cp-v3.3/#1.4.2-prohibited-certificate-uses https://letsencrypt.org/documents/isrg-cp-v3.3/#1.4.2-prohib... [2]: https://letsdebug.net/ https://letsdebug.net/ [3]: https://github.com/letsdebug/letsdebug https://github.com/letsdebug/letsdebug