If you use an older computer with Microsoft Windows such as Windows 7 or Windows 8 and have your computer set to do automatic updates, do not assume they are all getting done. Check to see how recent the dates actually are on installed updates. I discovered back in March that my computer had quit installing updates automatically, and that failure to automatically install updates is a known issue. You don't know they are not getting installed unless you check, it does not tell you it is no longer installing updates.
In order to be sure you have the current updates, go to Control Panel>Windows Update>Check for updates. If it says you are up to date, good. If it runs and runs, let it keep running even if it has to run 24 hours (in other words do not shut it off overnight) until it completes. It took 20 hours for mine to complete after not being updated for 6 months because the automatic update feature quit.
If you are using XP, updates have been released for that, too, be sure to install them.
I am concerned that the news reports about the recent ransomware attacks advise people to update their software, but none that I have heard have mentioned there can be a problem with the automatic update feature.
Do not assume you are up to date. Check.