The Sunderland player, 34, has made six appearances for the managerless club and will now remain at Brunton Park until December 13.
"We need strong characters and we need experience and Kavs brings us both of those," caretaker manager Greg Abbott told the club's official website.
"On top of that he's a very good footballer as well, so it's good news for everybody. Hopefully in his next month we will all see the upturn in results."