5 ms·

The simple solution would be to have independent entities offer trust assertions about CAs and to allow users to consider multiple entities' views in their deci

The simple solution would be to have independent entities offer trust assertions about CAs and to allow users to consider multiple entities' views in their decision about whether to trust. It's surprising this doesn't exist yet when the attack vector is so clear.

tptacek 2y ago
This is something more akin to a client software bug than a WebPKI issue. Any alternative PKI scheme you could come up with would still be subject to Microsoft cutting deals.
- silotis 2y ago
  With DNSSEC + DANE Brazil would not have needed to make any deal with MS to be able to issue certs for .br domains and they would not have been able to issue a cert for google.com. Admittedly DNSSEC has issues to put it mildly, but it does serve as a counterexample to your claim.
- 8organicbits 2y ago
  Can you explain? I think the parent is suggesting that users should be able to tune their trust stores. I'd imagine that trusting only the CAs that are in all the major trust stores (Google, Microsoft, Mozilla, and Apple) would be a reasonable policy. Few websites would choose a CA that falls outside that group.
  - tptacek 2y ago
    Users can tune their own trust stores.
    - 8organicbits 2y ago
      Is there a way to do it that isn't tedious? I'm not familiar with tooling beyond the UI browsers offer, which doesn't match the experience I was trying to describe.
      - salawat 2y ago
        I mean... It's as easy as getting SSL certs and importing them into a trust store/adding them to a directory. The hard part is getting the people you want to establish a trust relationship with to give you a copy of their key. Web of Trust was the answer to logistical key distribution problem. The idea being there would be an organization that would vet people and vouchsafe their cryptographic material for everyone else. The problem of course, is that the more invisible this is to users, and the more unintuitive the actual mechanics, the more valuable cracking the CA's becomes for hostile actors because of the ensuing blast radius compared to the boast radius that would result from theoretically getting the practice of key exchange in the public, and getting them to internalize the act of creating their own trust networks. Of course, if you have dreams or fantasies of being able to control people, none of the work that goes into educating the populace is ever going to be endorsed, because once everyone realizes that they can at least assure their own safety by not delegating their cryptography, the entire idea of eacesdropping as a third-party by tapping the line is unmade. Which is not a popular state of affairs universally.
        8organicbits 2y ago
        Web of trust is way more ambitious than what I'm talking about. Key distribution for the Apple, Microsoft, Google, and Mozilla trust stores is already a solved problem and works well at scale already. However, if you don't trust the inclusive nature of Microsoft's trust store and prefer Chrome's, there should be a tool to swap out trust stores. I don't think such a tool exists yet.
        resters 2y ago
        Right. I'm imagining a tool that would let users impose choices such as the following: - Accept any certs trusted by Bruce Schneier unless they are not trusted by tptacec - Do not accept new certs for top 1000 domain names unless they are over 7 days old and trusted by the Mozlla Foundation Various experts could create the rules they use to decide which certs or CAs they trust and users could decide which high profile authority figures or institutions they want to trust. One example might even be "Bruce Schneier paranoid version" I think this doesn't exist because of the following: 1) technically it is possible to do it today with the existing tools, even though nobody does it 2) the negative impact of trusting certs one shouldn't is low for the average user 3) sophisticated users already take precautions and are rarely fooled I think for something like this to work it would have to be extremely simple. Surely there would be the same phenomenon as "Dr. Oz" in the realm of cyber secruity. Maybe the 'Kevin Rose settings" would be popular, etc. But that would still open the door to distributed trust which is an improvement over blanket trust of large corporate entities.
deleted 2y ago
[deleted]
will4274 2y ago
It'd be a simple enough browser plugin to build - a tool that checks multiple trust stores when rendering a page. Probably it already exists. The problem is between the keyboard and the chair. Users struggle to understand SSL already. Browsers decided that the distinctions between EV, DV, and OV were too complex and hid them. What will your grandmother think when she opens up her bank and your browser plugin shows a greenish yellow trust indicator because the cert is trusted by Google, Apple, and Microsoft, but not Mozilla? Unfortunately, trust is binary. Your grandmother click on the bank bookmark and either sees her banking websites or sees a scary warning.

tptacek 2y ago

This is something more akin to a client software bug than a WebPKI issue. Any alternative PKI scheme you could come up with would still be subject to Microsoft cutting deals.

silotis 2y ago
With DNSSEC + DANE Brazil would not have needed to make any deal with MS to be able to issue certs for .br domains and they would not have been able to issue a cert for google.com. Admittedly DNSSEC has issues to put it mildly, but it does serve as a counterexample to your claim.
8organicbits 2y ago
Can you explain? I think the parent is suggesting that users should be able to tune their trust stores. I'd imagine that trusting only the CAs that are in all the major trust stores (Google, Microsoft, Mozilla, and Apple) would be a reasonable policy. Few websites would choose a CA that falls outside that group.
- tptacek 2y ago
  Users can tune their own trust stores.
  - 8organicbits 2y ago
    Is there a way to do it that isn't tedious? I'm not familiar with tooling beyond the UI browsers offer, which doesn't match the experience I was trying to describe.
    - salawat 2y ago
      I mean... It's as easy as getting SSL certs and importing them into a trust store/adding them to a directory. The hard part is getting the people you want to establish a trust relationship with to give you a copy of their key. Web of Trust was the answer to logistical key distribution problem. The idea being there would be an organization that would vet people and vouchsafe their cryptographic material for everyone else. The problem of course, is that the more invisible this is to users, and the more unintuitive the actual mechanics, the more valuable cracking the CA's becomes for hostile actors because of the ensuing blast radius compared to the boast radius that would result from theoretically getting the practice of key exchange in the public, and getting them to internalize the act of creating their own trust networks. Of course, if you have dreams or fantasies of being able to control people, none of the work that goes into educating the populace is ever going to be endorsed, because once everyone realizes that they can at least assure their own safety by not delegating their cryptography, the entire idea of eacesdropping as a third-party by tapping the line is unmade. Which is not a popular state of affairs universally.
      - 8organicbits 2y ago
        Web of trust is way more ambitious than what I'm talking about. Key distribution for the Apple, Microsoft, Google, and Mozilla trust stores is already a solved problem and works well at scale already. However, if you don't trust the inclusive nature of Microsoft's trust store and prefer Chrome's, there should be a tool to swap out trust stores. I don't think such a tool exists yet.
        resters 2y ago
        Right. I'm imagining a tool that would let users impose choices such as the following: - Accept any certs trusted by Bruce Schneier unless they are not trusted by tptacec - Do not accept new certs for top 1000 domain names unless they are over 7 days old and trusted by the Mozlla Foundation Various experts could create the rules they use to decide which certs or CAs they trust and users could decide which high profile authority figures or institutions they want to trust. One example might even be "Bruce Schneier paranoid version" I think this doesn't exist because of the following: 1) technically it is possible to do it today with the existing tools, even though nobody does it 2) the negative impact of trusting certs one shouldn't is low for the average user 3) sophisticated users already take precautions and are rarely fooled I think for something like this to work it would have to be extremely simple. Surely there would be the same phenomenon as "Dr. Oz" in the realm of cyber secruity. Maybe the 'Kevin Rose settings" would be popular, etc. But that would still open the door to distributed trust which is an improvement over blanket trust of large corporate entities.

deleted 2y ago

[deleted]

will4274 2y ago

It'd be a simple enough browser plugin to build - a tool that checks multiple trust stores when rendering a page. Probably it already exists. The problem is between the keyboard and the chair. Users struggle to understand SSL already. Browsers decided that the distinctions between EV, DV, and OV were too complex and hid them. What will your grandmother think when she opens up her bank and your browser plugin shows a greenish yellow trust indicator because the cert is trusted by Google, Apple, and Microsoft, but not Mozilla? Unfortunately, trust is binary. Your grandmother click on the bank bookmark and either sees her banking websites or sees a scary warning.