With all due respect, I disagree with the general consensus from the replies that “user education” should be the most important item in the list. This thinking is no only dangerous but also it goes against common sense.
Even the most security conscientious users will click on an e-mail that comes from their bosses, contact, supplier or client. I see this ALL THE TIME! it’s easy for users to distrust an e-mail that comes from an unknown source, in fact I have seen very little incidents where a user has opened an attachment or clicked a link on e-mail from an unknown sender.
Last week I had a close call with a client that I consider very security aware and it’s a smart person, however his boss forwarded an e-mail that his boss himself did not open but was asking this person to find out what it was because the subject says “Past Due Invoice”. Sure enough the subordinate opened the PDF attachment.
My policy is ZERO TRUST, I have to assume people are stupid when it comes to computer technology (most are), I have to assume that at some point they will eventually open an attachment (most will). Therefore, I never trust the user (trained or not)
So what can I do? The answer was simple in my case.
GET A SECURITY SOLUTION THAT BLOCKS EVERYTHING EVEN LEGIT APPLICATIONS!!!
Yes, I prefer 1000 times to get a 100 calls about a legit application being blocked that ONE CALL from a user asking why all the files inside the network drive look weird and he cannot open any file. Because they are ALL encrypted stupid !!!
It’s 1000 times less stressful, easier and faster to allow a false positive than deal with a Ransomware infection. You do the math.
I sleep better these days knowing that my Security Solution trust NOTHING unless I say so.
Get an EDR Solution with NextGen A.I. AV like Sentinel ONE (If you cannot afford CrowStrike Falcon) and combine it with a threat hunter like Huntress and I can assure you the only calls you will get will be from users asking why they cannot open WinRAR, 7Zip or some bootlegged PDF editor.
Better be the asshole than be the victim and feeling sorry for yourself.
Take care.