I saw two things recently. First, CU25 for SQL Server 2017 was released. I realized that I was CU8 locally, so I had work to do. Second, I noticed that SQL Server 2016 fell out of mainstream support on 13 Jul, 2021. Amazing that it's been around for 5 years already and has moved into Extended support. We'll still get security updates, but nothing will be fixed from that version, which it seems many people are running.
Microsoft also announced they will put out a final Service Pack for SQL Server 2016. I am glad to see that, as I've often wanted to know there is a final patch that is released for each version, as I can know when I'm done patching.
Today I'm wondering if you track this at all. Do you actively look to ensure your instances are patched? Are you on a schedule of some sort, maybe matching Microsoft's every-other-month pace, or perhaps just a few times a year? Or is this more ad hoc? When I go visit companies, I often find instances at all different levels, often without any reasoning as to why systems aren't consistently patched.
I used to try and ensure we patched every quarter, though certainly, I faced resistance from some business owners of systems over the worry that a patch might break something. Valid concerns back then, and still somewhat valid today, though if a patch gets through a few months without reports of issues, it's probably safe for most systems. Still, make sure you test, especially for business critical workloads.
These days, with so many hacking attempts, ransomware distribution channels, and no end to phishing, it makes sense to stay on top of patches and make sure you are up to date or at least planning to do so. Some of the high-profile hacks, like the Equifax one, have occurred on systems where patches were available but not applied. I don't know that many of the patches are closing holes in SQL Server, but there are definitely issues with Windows where you would want to ensure your host OS was patched. Maybe that's something you ought to check on today and ensure you have a plan to apply those updates.