My answer... it's a bass... it's suppose to have horrible action.
But seriously... I wouldn't put too much into it. It's a Squire... an entry level guitar... normally when stuff starts to go wrong... ie. fret wear, bum electronics, neck warping... and such... It's simply time to move on to another guitar... If it needs a fret job, crowning, leveling... you might as well leave it how it is. It's not worth the money... that's my opinion though.
Try raising the bridge saddles as high as you can with out them buzzing... Then straighten the neck with a truss rod adjustment... This will pull the strings into the neck... giving you good action on the low frets (1-7) and give you the best action that you can get without buzz on the higher frets. If it still is buzzing... take it in and have it looked at... just don't go spending a bunch of money to fix it...