There are very few one click total compromises out there.
Most of the time clicking on the link will get to a phishing page to harvest credentials or prompt to download a zip or pdf which has the actual malware exploit/payload.
In my time as a cybersecurity professional, my approach is always to blame the system, not the person.
If they clicked on a phishing link: 1) that email should never have reached their inbox, 2) that link should never have loaded, and 3) our awareness training is not up to snuff.
We have test-phishing mails sent by our IT-Sec team on a regular basis. There's usually an obvious one and a better made one.
First round 10% clicked the obv. one, 99% the good one.
We had a lot of trainings after that.
Last year the numbers went down to 5% and 80%.
If your security concept relies on both of these numbers being zero, you're an incompetent hack trying to shift the blame on end users instead of doing your job.
Welcome to corporate phishing emails, then, where the page that loads scolds you for being an idiot and submits your name to the boss for automated remedial phishing training, which must be completed lest it also tells HR...
Adversaries are well prepared. Go restore your cold archive from tape, petabytes worth, see how long it'll take you. See how much data you missed before the last snapshot.
Ransomware is no joke and nobody is actually prepared for it.
As a system admin I can sympathize, but honestly I don't see any resolution that will fix this in the short or longterm. You just have to accept that the reality of computing is that if you interact with external data in a way that runs unfriendly code, you can/probably will compromise your system. It's just a consequence of making rocks smart.
Yes but not every user needs access to every system all the time and there should be alerts set up for logins outside of working hours, expected devices and IPs.
There should be behavior based alerts, for example, why is the HR lady opening PS?
There are many things that can be done to secure the systems post-compromise.
Oh, of course. But that's for compromises utilizing tool chains and exploits you're aware of. Zero day exploits are commonplace nowadays and often utilize complex tool chains to avoid detection or circumvent security posture. It's all a matter of how sophisticated the attack is and it all becomes a lot easier to do if you've got user level run permissions due to some user clicking a phishing email and tossing their creds in it or launching a random pdf with an embedded payload.
Maybe not finacilly or legally but image wise it can. Depending on the company and the people involved a company can 100% loose a lot image wise and in consequence, money wise