4 ms·

Who cares if it's a pain? User security is vastly more important than saving companies from the mild inconvenience of changing certs.

by wyager 10y ago

tptacek 10y ago
The fact that they're honoring previous certificates is a good thing. It's a demonstration from Mozilla and Google that CAs with large customer bases have very little leverage in disputes like this: Mozilla will respond with the corrective measure that causes maximum pain for the CA business and minimal pain for the CA's previous customers.
daenney 10y ago
You forget things like certificate pinning which can make sites inaccessible for long durations of time if the user doesn't visit said website during this transition period. I'm not super convinced about the user security argument either. Sure, they backdated SHA-1 certificates and that's nasty but those certificates still expire at a reasonable time in the near future and will soon enough not be accepted by browsers at all or show up with scary UI warnings. That said I don't agree or condone what they did.
- makomk 10y ago
  Mozilla and the other browser developers' position seems to be that issuing SHA-1 certificates when they've said SHA-1 certificates should not be issued is a cardinal sin - never mind that this would break payments infrastructure. They eventually agreed to an exception process after Tyro's payments systems would presumably have stopped working if WoSign hadn't issued them a certificate.
  - jcranmer 10y ago
    The SHA-1 deprecation wasn't a secret: it was decided back in October, 2014. In February 2016, one provider basically said "oops, we screwed up, how can we get a SHA-1 certificate?", whereupon the answer was a one-off exception that would be notated as "yes, Symantec violated the rules, but everyone agreed to let this exception go through." This exception was converted into a more formal exceptions approval in June. Tyro's certificate would have expired on June 9, 2016 if I'm reading the timeline right. There is nothing that would have prevented them from doing what WorldPay did and approach the CAB themselves, or become vigorously involved in the ongoing discussion (the proposal document for the process was made June 3, 2016). On the other hand, as the IT mantra goes, failure to plan on your part does not constitute an emergency to plan on my part. The evidence is that Tyro updated its certs at the last minute, found that they couldn't get the SHA-1 they needed, and basically shopped around until they found someone who gave it to them (while lying about it!), instead of, say, making sure to request a certificate in late December to maximum the transition time available. The great sin is not so much that they issued the SHA-1 certificate, but that they agreed not to do it, and when someone needed one, rather than bring it up with the CAB Forum, they issued one and lied about their compliance. The REALLY great sin is that they appear to have built an entire system to do the backdating, rather than applying one-offs. Browsers can forgive CAs when they fess up to their mistakes. It's when they lie about them that they get really pissed off.
geofft 10y ago
Is user security actually improved by causing all WoSign- and StartCom-signed sites to show certificate warnings? It seems to me like it is reduced: 1. Your browser is no longer capable of telling you whether it's a legitimate WoSign- or StartCom-signed certificate (they behaved inappropriately, but they never intentionally signed one site's cert for someone not affiliated with the site) or a completely random certificate. 2. People clicking through SSL warnings is one of the bigger risks to user security in practice. Teaching people (especially people in their target markets) that they need to click through these warnings to get to their websites will have a very long-term negative effect on user security for a long time to come.

Who cares if it's a pain? User security is vastly more important than saving companies from the mild inconvenience of changing certs.

by wyager 10y ago

Who cares if it's a pain? User security is vastly more important than saving companies from the mild inconvenience of changing certs.

tptacek 10y ago

The fact that they're honoring previous certificates is a good thing. It's a demonstration from Mozilla and Google that CAs with large customer bases have very little leverage in disputes like this: Mozilla will respond with the corrective measure that causes maximum pain for the CA business and minimal pain for the CA's previous customers.

daenney 10y ago

You forget things like certificate pinning which can make sites inaccessible for long durations of time if the user doesn't visit said website during this transition period. I'm not super convinced about the user security argument either. Sure, they backdated SHA-1 certificates and that's nasty but those certificates still expire at a reasonable time in the near future and will soon enough not be accepted by browsers at all or show up with scary UI warnings. That said I don't agree or condone what they did.

makomk 10y ago
Mozilla and the other browser developers' position seems to be that issuing SHA-1 certificates when they've said SHA-1 certificates should not be issued is a cardinal sin - never mind that this would break payments infrastructure. They eventually agreed to an exception process after Tyro's payments systems would presumably have stopped working if WoSign hadn't issued them a certificate.
- jcranmer 10y ago
  The SHA-1 deprecation wasn't a secret: it was decided back in October, 2014. In February 2016, one provider basically said "oops, we screwed up, how can we get a SHA-1 certificate?", whereupon the answer was a one-off exception that would be notated as "yes, Symantec violated the rules, but everyone agreed to let this exception go through." This exception was converted into a more formal exceptions approval in June. Tyro's certificate would have expired on June 9, 2016 if I'm reading the timeline right. There is nothing that would have prevented them from doing what WorldPay did and approach the CAB themselves, or become vigorously involved in the ongoing discussion (the proposal document for the process was made June 3, 2016). On the other hand, as the IT mantra goes, failure to plan on your part does not constitute an emergency to plan on my part. The evidence is that Tyro updated its certs at the last minute, found that they couldn't get the SHA-1 they needed, and basically shopped around until they found someone who gave it to them (while lying about it!), instead of, say, making sure to request a certificate in late December to maximum the transition time available. The great sin is not so much that they issued the SHA-1 certificate, but that they agreed not to do it, and when someone needed one, rather than bring it up with the CAB Forum, they issued one and lied about their compliance. The REALLY great sin is that they appear to have built an entire system to do the backdating, rather than applying one-offs. Browsers can forgive CAs when they fess up to their mistakes. It's when they lie about them that they get really pissed off.

geofft 10y ago

Is user security actually improved by causing all WoSign- and StartCom-signed sites to show certificate warnings? It seems to me like it is reduced: 1. Your browser is no longer capable of telling you whether it's a legitimate WoSign- or StartCom-signed certificate (they behaved inappropriately, but they never intentionally signed one site's cert for someone not affiliated with the site) or a completely random certificate. 2. People clicking through SSL warnings is one of the bigger risks to user security in practice. Teaching people (especially people in their target markets) that they need to click through these warnings to get to their websites will have a very long-term negative effect on user security for a long time to come.