I have anothers sites running in the same host and Avast doesnt block it. So how can you explain that?
You really don't have any clue at all how things are working as it seems.
A host has multiple servers.
That means one can be running the latest software while another isn't.
I can understand that you don't want your website(s) to be blocked.
If you did, you would not have set them up
However, the block is there to protect users.
The solution is really simple:
Fix the problems and avast will remove the block.