Nothing, although it's more mitigate than prevent per se. They simply did not have alerting set up against the CT logs. It is one of the lessons they highlighted in their own postmortem.
Yeah I suppose the prevent part came from the Browser/CA forum giving the CA that did it the death penalty like they did for Kazakhstan's CA in 2015 but if the men with guns point them at executives of browser providers and say "trust this CA or else" then CT is more of a cosmetic system than anything else.
Yeah I suppose the prevent part came from the Browser/CA forum giving the CA that did it the death penalty like they did for Kazakhstan's CA in 2015 but if the men with guns point them at executives of browser providers and say "trust this CA or else" then CT is more of a cosmetic system than anything else.