Free certificates for IP addresses: security problem or solution? www.malwarebytes.com/blog/news…

Let’s Encrypt has announced its issued its first certificate for an IP address. Why that’s significant deserves a little explanation.

You may have run into Let’s Encrypt certificates many times without realizing it. When you see a padlock icon in your browser’s address bar, it means the site is using a certificate to secure your connection. These certificates are “digital passports” that websites use to prove their identity and to encrypt the data sent between your browser and the website.

Traditionally, these certificates have only been issued for domain names (like malwarebytes.com). Now, Let’s Encrypt has started issuing certificates for IP addresses, which are the numerical labels (like 192.0.66.233) that computers use to find each other on the internet.

The advantages of providing certificates for IP addresses are clear. Since some browsers will refuse to open sites without a certificate, it provides a safer way to access your website if you don’t have a domain name at all. It also allows you to use your browser to remotely access home devices like network-attached storage (NAS) servers and Internet-of-things (IoT) devices.

But most home users are unlikely to access a site by using the IP address. Domain names are much easier to remember (most of them anyway) and Domain Name System (DNS) translates domain names to IP addresses for us without a lot of problems.

And while IP addresses can change, DNS will make sure that our browser can still find the domain we want to visit. This is one reason why Let’s Encrypt will only issue short-term certificates for IP addresses: The certificates will be valid for just six days, a move designed to minimize the risk window in the event of a key compromise and to encourage automated certificate renewal practices.