Occasionally you will need to reset everyone’s password to make sure your site is staying secure. I created an emergency password reset plugin some years ago that does that and emails everyone to let them know.
It can also change SALTs too – they are random gobbledygook that are used to salt sensitive data before encrypting it for extra security.
It’s available FREE on the WordPress plugin repository or search “Emergency Password reset” from Dashboard>Plugins>Add Plugin.
As you can see it is pretty easy to use!