New York announced the transaction on Saturday. The Giants placed fourth-year center Weston Richburg on injured reserve in a corresponding transaction.
Richburg went down with a concussion on Oct. 1 and hasn't played in a game since. He was designated as out on Friday for Sunday's contest against the Los Angeles Rams. He has missed four consecutive games.
Scott originally joined the Giants on Aug. 24. He had five tackles and a pass defensed in the Giants' fourth preseason game this year against the New England Patriots. Scott was waived on Sept. 1 before joining the Giants' practice squad on Sept. 3. The 5 foot 11, 195 pound defender has never played in an NFL regular-season contest. He entered the NFL in 2015 as an undrafted rookie free agent signing by the Dallas Cowboys. He previously spent time with the practice squads of the Cowboys and Cleveland Browns. Scott signed with the Washington Redskins on Aug. 3 but was later released.
New York needs depth at cornerback after Janoris Jenkins was suspended indefinitely. Donte Deayon is listed as questionable for Sunday's game after he injured his ankle in Thursday's practice session.
Richburg, 25, was a second round pick by the Giants in the 2014 NFL Draft. Before this season, he had only missed one game in his NFL career. He had started 46 of a possible 48 games in his three previous seasons with the Giants.