These f*cking mice.

Finally thought the mice were gone. Been around a month or two since I last saw any sign of them in my car. Drove to school in the dark, and when I parked I see all this foam and white papery stuff had been pushed out of all of my vents. I am very pissed, but does anyone know what this stuff could be? I am hoping it is the cabin air filter, but I cannot check right now as I’m in school. Most likely gonna want to replace whatever was torn up.