Hello!
Your possibility of receiving an acceptance in a German university is inversely proportional to the number of arrears you had during your under graduation.
However, there are exceptions, if you are applying for a program where the competition /demand is meagre, you would yet get admission. For instance, we had applied for one of our student to BTU Cottbus in the year 2016 with 23 arrears for the course named MSc in Environmental Engineering. And, he did receive admission!
So, if you do a little analysis on Supply and demand on the program that you are willing to apply, you would know your chances.
Thanks in advance.