For those who want to read the original journalism and not a blog's re-hash of someone else's hard work:
https://www.forbes.com/sites/thomasbrewster/2020/01/15/the-f...
https://www.forbes.com/sites/thomasbrewster/2020/01/15/the-f...
(to be clear: if Forbes handled their ads on their own or used ad networks that invest in the security of their platform, I'd actually probably bite the bullet, but if I visit the site on mobile and end up being redirected to another "your phone is infected!" ad exploiting their current provider... I'll keep steering clear without ublock enabled.)
Image copy of the article for the interested.
So basically bad actors are hijacking the ad network that Forbes is using because it's a poorly secured ad network.
I didn't realize that was what was going on but that explains a great deal.