I’m getting more and more upset by the advertising, I’ll probably get rid of avast >:(
You can disable the ads in the paid versions: Avast GUI → Settings → Personal Privacy
Since you don’t state what Avast version you have, I would have to guess Avast Free ?
If not then these product ads can be disabled in the paid versions of Avast as mentioned by Asyn.
However, these settings do not prevent all notification popups, such as the new “Important Cybersecurity Information from avast”.
Even if this kind of information is legitimate, the customer (paid versions) should be able to choose whether to be notified or not … at least that a (general protection) window does not open wide when not requested, but can be opened manually in an area of the application or better in the “notifications” area. :-\
edit:On the other hand, for those who have involuntarily closed the window or who would like to see it again, it is difficult to find it at another better time … later. 
They would not have this problem if the information was in the notifications.
Agreed…!!
I would go a step further and disable these promotions by default on paid versions.
All we see in the forums are how do I bl00dy remove these ads from paid users, not how do I enable ads/promotions. I feel this is more likely to drive paying customers away rather than persuade them to purchase other paid products.
If avast has chosen this policy, I think they have their reason, they must have their own statistical tools which should support their choice to leave the boxes ticked by default.
There are probably more customers who buy other tools than customers who run away.
If they make a mistake about the policy adopted, they are not good businesses.
Dev-Info: It was a one-time campaign. […] Let’s consider it if it’s going to be some recurring campaign.