The 18-year-old will remain with the Championship club until their clash with Sheffield Wednesday on December 2, covering a total of eight league fixtures.
The Bluebirds' move follows injuries to Craig Bellamy and Tommy Smith, who are expected to be out for a couple of weeks, according to manager Malky Mackay.
Frei made his debut for Fulham last season and featured in 20 competitive games for the Premier League outfit.







