Let’s Encrypt will be reducing the validity period of the certificates we issue. We currently issue certificates valid for 90 days, which will be cut in half to 45 days by 2028.
This change is being made along with the rest of the industry, as required by the CA/Browser Forum Baseline Requirements, which set the technical requirements that we must follow. All publicly-trusted Certificate Authorities like Let’s Encrypt will be making similar changes. Reducing how long certificates are valid for helps improve the security of the internet, by limiting the scope of compromise, and making certificate revocation technologies more efficient.
But can you imagine the load on their servers should it come to this? And god forbid it goes down for a few hours and every person in the world is facing SSL errors because Let’s Encrypt can’t create new ones.
This continued shortening of lifespans on these certs is untenable at best. Personally I have never run into a situation where a cert was stolen or compromised but obviously that doesn’t mean it doesn’t happen. I also feel like this is meant to automate all cert production which is nice if you can. Right now, at my job, all cert creation requires manually generating a CSR, submit it to a website, wait for manager approval, and then wait for creation. Then go download the cert and install it manually.
If I have to do this everyday for all my certs I’m not going to be happy. Yes this should be automated and central IT is supposed to be working on it but I’m not holding my breath.
I doubt they will drop below 1-2 weeks. Any service outage would turn into a ddos when service was restored.
The entire renewal process is fairly cheap, resource wise. 7 day certificates are already a thing.
In terms of bandwidth you could easily renew a billion certificates a day over a gigabit connection, and in terms of performance I recon even without specialized hardware a single system could keep up with that, though that also depends on the signature algorithms employed in the future of course.
The dependence on these servers is the far bigger problem I’d say.
This shortening of lifetimes is a slow change, so I hope there will be solutions before it becomes an issue. Like keeping multiple copies of certificates alive with different providers, so the one in use can silently fall through when one provider stops working. Currently there are too few providers for my taste, that would have to improve for such a system to be viable.
Maybe one day you’ll select a bundle of 5 certificate services with similar policies for creating your certificate the way you currently select a single one in certbot or acme.sh