The 20-year-old, who signed for the Clarets from Leyton Orient in the summer, is yet to feature for the npower Championship club since making the move.
U's boss Joe Dunne told the club's official website: "George is a very quick young player who has great attacking qualities.
"He has caused us many problems in the past when he was playing for Leyton Orient and we are pleased to have him in the building in terms of adding quality and hunger to the team."
Monday also saw U's midfielder John-Joe O'Toole join Bristol Rovers on loan for a month.
- Sports & Recreation
- Leyton Orient