Here are the latest versions of these important plugins as of:

1-9-2018

Adobe Flash*

28.0.0.137

Adobe Reader 18.009.20050
Java Runtime Engine 9.0.1
Mozilla Firefox 143,672.0.7 (Just kidding... It's 57.0.4)
   

*If you are using Firefox, you will need a separate version of the Flash update in addition to the one for IE.

Beta versions not considered.

Keep the above programs up to date, along with your OS and virus definitions, and you are likelier to be a happy camper.