Callum McGregor's Celtic will be away for the second leg while Igor Jesus' Forest will be at home for the return game of their tie
Celtic will play Stuttgart and Nottingham Forest will face Fenerbahce in two-legged play-offs to reach the last 16 of the Europa League.
Martin O'Neill's side could also have been drawn against Hungarian club Ferencvaros, managed by Robbie Keane, but will instead face the Bundesliga club.
The first leg will be at Celtic Park and the winners of the tie will play either Porto - who defeated O'Neill's side in the 2003 Uefa Cup final - or another Portuguese side Braga in the last 16.
Forest, whose alternative tie was against Greek side Panathinaikos, will play Midtjylland or Real Betis if they progress past the Turkish club.
