UEFA says its disciplinary panel judged charges of "illicit banner" and fireworks being lit at a 1-1 draw in Sweden in October.
Malmö was put on one year's probation and warned a section of the stadium could be closed for one game if offenses are repeated.
UEFA fined the club 66,000 euros ($73,000) for charges including fans throwing objects.
Though in different countries, Copenhagen and Malmö are separated by a 40-kilometer (25-mile) drive connected by a bridge over the Oresund strait.
The Dec. 12 return in Denmark is the final game in a three-way fight with Dynamo Kyiv to advance from their group.
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