An Israeli surveillance technology firm has run a large-scale operation to infect mobile phones with spyware using online advertisements to hack the devices, researchers said on Thursday.
Here is a bit more information that might help, I posted this in privacy too.
On Android, my ad-blocking strategy is to use uBlock Origin with Firefox, and to not tolerate apps with built-in ads to begin with (getting most of them from F-Droid).
I try to do the same, but not everyone is able to be in that position