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.

  • cron@feddit.org
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    8 小时前

    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.

    • False@lemmy.world
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      5 小时前

      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.

      • cron@feddit.org
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        4 小时前

        No, these are completely separate issues.

        • CRL: protect against certificates that have their private key compromised
        • CT: protect against incompetent or malicious Certificate Authorities.

        This is just one example why we have certificate transparency. Revocation wouldn’t be useful if it isn’t even known which certificates need revocation.

        The National Informatics Centre (NIC) of India, a subordinate CA of the Indian Controller of Certifying Authorities (India CCA), issues rogue certificates for Google and Yahoo domains. NIC claims that their issuance process was compromised and that only four certificates were misissued. However, Google is aware of misissued certificates not reported by NIC, so it can only be assumed that the scope of the breach is unknown.

        Source

      • Auli@lemmy.ca
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        5 小时前

        Or the more likely a rouge certificate authority giving out certs it shouldn’t.

      • cron@feddit.org
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        7 小时前

        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:

        • do not use public certificates
        • use wildcard certificates only
        • Burnoutdv@feddit.org
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          6 小时前

          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