Well, at first glance it looks like a cross between a black-bear cub and something.
If it's still not fully grown then there is a chance that it's at least partly a schipperke or something similar. There are several small Northern European breeds that look kind of similar. The white spot on the chest makes me suspect that it's mix. You might see a white spot on a black dog like that in something like a black german shepherd (see picture). The one in the picture is a puppy and unless yours is also a puppy I don't see how it could be a german shepherd.