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.
So what’s the floor here realistically, are they going to lower it to 30 days, then 14, then 2, then 1? Will we need to log in every morning and expect to refresh every damn site cert we connect to soon?
It is ignoring the elephant in the room – the central root CA system. What if that is ever compromised?
Certificate pinning was a good idea IMO, giving end-users control over trust without these top-down mandated cert update schedules. Don’t get me wrong, LetsEncrypt has done and is doing a great service within the current infrastructure we have, but …
I kind of wish we could just partition the entire internet into the current “commercial public internet” and a new (old, redux) “hobbyist private internet” where we didn’t have to assume every single god-damned connection was a hostile entity. I miss the comraderie, the shared vibe, the trust. Yeah I’m old.
Automate your certificate renewals. You should be automating updates for security anyway.
This is one of the reasons they’re reducing the validity - to try and convince people to automate the renewal process.
That and there’s issues with the current revocation process (for incorrectly issued certificates, or certificates where the private key was leaked or stored insecurely), and the most effective way to reduce the risk is to reduce how long any one certificate can be valid for.
A leaked key is far less useful if it’s only valid or 47 days from issuance, compared to three years. (note that the max duration was reduced from 3 years to 398 days earlier this year).
From https://www.digicert.com/blog/tls-certificate-lifetimes-will-officially-reduce-to-47-days:
LE is beta-testing a 7-day validity, IIRC.
No, those are expected or even required to be automated.
7-day validity is great because they’re exempt from OCSP and CRL. Let’s Encrypt is actually trying 6-day validity, not 7: https://letsencrypt.org/2025/01/16/6-day-and-ip-certs
Another feature Let’s Encrypt is adding along with this is IP certificates, where you can add an IP address as an alternate name for a certificate.
Ah, well. I only remembered something about a week.
The best approach for securing our CA system is the “certificate transparency log”. All issued certificates must be stored in separate, public location. Browsers do not accept certificates that are not there.
This makes it impossible for malicious actors to silently create certificates. They would leave traces.
Isn’t this just CRL in reverse? And CRL sucks or we wouldn’t be having this discussion. Part of the point of cryptographically signing a cert is so you don’t have to do this if you trust the issuer.
Cryptography already makes it infeasible for a malicious actor to create a fake cert. The much more common attack vector is having a legitimate cert’s private key compromised.
This seems like a good idea.
The only disadvantage I see is that all my personal subdomains (e.g. immich.name.com and jellyfin) are forever stored in a public location. I wouldn’t call it a privacy nightmare, yet it isn’t optimal.
There are two workarounds:
But how to automate wildcard certificate generation? That requires a change of the txt record and namecheap for instance got no mechanism for that to automatically happen on cert bot action
There are some nameserver providers that have an API.
When you register a domain, you can choose which nameserver you like. There are nameservers that work with certbot, choose one that does.
The current plan is for the floor to be 47 days. https://www.digicert.com/blog/tls-certificate-lifetimes-will-officially-reduce-to-47-days, and this is not until 2029 in order to give people sufficient time to adjust. Of course, individual certificate authorities can choose to have lower validity periods than 47 days if they want to.
Essentially, the goal is for everyone to automatically renew the certificates once per month, but include some buffer time in case of issues.
Not exactly what you mean because there are also bad actors but take a look at i2p, in some ways it feels like an retro internet.
Seeing as most root CA are stored offline compromising a server turned off is not really possible.
I’m more annoyed that I have 10 year old gear that doesn’t have automation for this.
Oh, I’m really just pining for the days before the ‘Eternal September’, I suppose. We can’t go back, I know. :/