Three, Two, One, Liftoff on One-Year TLS Certificates

At the CA/Browser (CA/B) Forum in Bratislava, Slovakia, this week, Apple announced that beginning Sept. 1, newly issued publicly trusted TLS certificates are valid for no longer than 398 days. This followed a long history of the CA/B Forum community working to reduce certificate lifetimes and improve security, while balancing the needs of business owners in transitioning to shorter validity certificates.

In August 2019, CA/B Forum Ballot SC22 was introduced by Google to reduce TLS certificate validity periods to one year. CAs reviewed this proposal with their customers and produced thousands of comments from users, which mostly showed opposition, due to the additional work required by IT teams to handle shorter validity periods. The ballot failed in the Forum, which meant certificate maximum lifetimes remained at two years.

At one time, certificates were offered with a maximum validity of three years. A few years ago, they were reduced to two years. Fast forward to this week's Apple announcement, which ultimately does what ballot SC22 failed to do: reduce certificate lifetimes to one year.

Why did Apple unilaterally decide to enforce a shorter certificate lifetime? Their spokesperson said it was to "protect users." We know from prior CA/B Forum discussions that longer certificate lifetimes proved to be challenging in replacing certificates, in the case of a major security incident. Apple clearly wants to avoid an ecosystem that cannot quickly respond to major certificate-related threats. Short-lived certificates improve security because they reduce the window of exposure if a TLS certificate is compromised. They also help remediate normal operational churn within organizations by ensuring yearly updates to identity such as company names, addresses and active domains. As with any improvement, shortening of lifetimes should be balanced against the hardship required of certificate users to implement these changes.

Apple has now released its official Knowledge Base article on this subject which can be found here. What does this mean for website certificate users? For your website to be trusted by Safari, you will no longer be able to issue publicly trusted TLS certificates with validities longer than 398 days after Aug. 30, 2020. Any certificates issued before Sept. 1, 2020 will still be valid, regardless of the validity period (up to 825 days). Certificates that are not publicly trusted can still be recognized, up to a maximum validity of 825 days.

DigiCert agrees that shorter lifetimes help enhance the security of the ecosystem and has the tools necessary to help our customers automate the certificate lifecycle process. We support short-lived certificates, with lifetimes as short as a few hours for customers with advanced automation capabilities. Additionally, our CertCentral platform includes the ability to schedule and automate replacement of EV, OV and DV certificates. Using CertCentral admins may take advantage of continuous discovery, renewal notices, thorough API integration and documentation, as well as support for orchestration layers.

As certificate validity periods continue to decrease, automation will be a must for organizations' ability to manage shorter lifetimes. DigiCert is prepared with the industry's most advanced and reliable tools to help our customers take the necessary steps toward greater use of automation.

Learn more at https://www.digicert.com/campaigns/tls-best-practices-guide#help.