The 22-year-old has a wealth of experience for his age and signs for the Bluebirds following six years with Sky Bet Championship side Reading.
During that time he has played on loan at several clubs including Peterborough United, Luton Town and Gloucester City.
Moore made his Gloucester debut against Barrow back in 2014.
His honours include winning the Under-21 Premier League Cup with Reading in the 2013/14 season.