Its face looks like it might be related to the German Shepherd. I’m not sure about the curly hair on its back. Maybe it’s a husky of some kind, or has husky blood mixed with something else. In the dog world, when animals are not neutered or spayed, there are so many mixed breeds and mongrels because of the sex drive and zero discrimination when it comes to breed and background.
When left to themselves, animals of a similar size and type tend to breed indiscriminately, giving rise to any number of unique combinations. My current dog is a great example. The humane society labelled her as a terrier mix but no one can decide what kind of mix. I get guesses from people on the street varying all the way from beagle to wire hair terrier to Jack Russel terrier to hound dog.
Your picture is not the greatest when it comes to determining fine details such as type of fur so I can only stick with my earlier guess that it’s some kind of Shepherd dog or husky.