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.



Reducing the valid time will not solve the underlying problems they are trying to fix.
We’re just gonna see more and more mass outages over time especially if this reduces to an uncomfortably short duration. Imagine what might happen if a mass crowdflare/microsoft/amazon/google outage that goes on perhaps a week or two? what if the CAs we use go down longer than the expiration period?
Sure, the current goal is to move everybody over to ACME but now that’s yet another piece of software that has to be monitored, may have flaws or exploits, may not always run as expected… and has dozens of variations with dependencies and libraries that will have various levels of security of their own and potentially more vulnerabilities.
I don’t have the solution, I just don’t see this as fixing anything. What’s the replacement?
clearly the most secure option is to have certificates that are only valid for 30 seconds at a time
Let’s be extra safe. New cert per every request
Ephemeral diffie-hellman is exactly that, it’s part of TLS since I think 1.2
Well it should be as short as possible while still being practical. LE doesn’t have infinite server compute, renewal also takes some amount of time, plus if they make the validity too short people might stop using them (pretty evident judging from sentiment here) and move to other CAs and make what they do pointless.
45 days are still plenty of time yet people are already complaining. Does make me worry.