Sugar Maple disease
There is a phenomenon of rapid decline of maple trees, however they are usually declining slowly over several years: https://kentcoopextension.blogspot.com/2008/06/landscape-sudden-death-of-maples.html
I think the most common sources of decline are road salts and girdling roots from the tree being planted too deep.
The brown on the bark looks to be Bacterial Wetwood. http://apps.extension.umn.edu/garden/diagnose/plant/deciduous/poplar/branchessap.html
It is difficult to diagnose based on pictures, I suggest you contact a reputable arborist for a diagnosis. You might contact your city's forester and see if they could make a "house call."
The fungal-looking spots could be a canker, again an arborist would be able to advise.