I own a 1997 subaru legacy and in the front floor on both sides the rug gets wet when it rains even though it just sits in the driveway. Is this a common thing and what can I do to rectify it ?

Sound like one or more of your drains might be clogged. Rain can be seeping in from moon roof, windshield ,etc. Could also be drain on cowl to. I would bring to a your mechanic , auto body shop or dealership .

If you have a sun roof your drain lines may be clogged or broken. Best to take into dealer they have to take down the headliner to check the drain lines. Not sure how much this costs but i would call dealership and ask how much it would be.

Sounds like you have a leak that's causing your problem. Water could be coming in from the windshield or the Sun Roof (if you have one).