I see that the ducts for the fresh air intake for the furnace room go up to the attic and pull the air from there. There is no filter on the ends of the ducts. It seems to me the ducts shouldn't end in the attic this way. I would think that this will cause them to pull in dust and particles from the attic into my heating/cooling system and then pump that into the rest of the house for us to breathe...

It also seems to me that if it pulls the fresh air from the attic, it would pull hot air in the summer that needs to be cooled by the AC, and cold air in the winter that would need to be warmed...

Is this normal and I'm just off base, or should it be fixed?
If it should be fixed, should I just put some sort of filter on the open end of the ducts in the attic, or should I reroute them to pull fresh air from outside? Where?

Thanks